As a man ages their risk of prostate cancer increases. In the US, prostate cancer is the most frequent male cancer diagnosis, and the second leading cause of death. Although conventional treatment options have been shown to be helpful, they also come with a myriad of negative side effects. One common treatment for prostate cancer, androgen deprivation therapy, can cause numerous physical, mental, and emotional side-effects. One efficacious way to mitigate these negative side-effects is with exercise. Unfortunately, many healthcare providers never bother to address these issues, and if they do, it tends to be with pharmaceuticals, which have the potential to make matters worse. Exercise, a non-pharmacological approach, affects the body globally in a positive way, especially if it is prescribed to match the unique needs of the patient. The amount of evidence supporting its use for prostate cancer prevention and as adjunctive treatment is limited. However, the evidence is clear exercise will support the body in its fight against both mental and physical chronic disease, and most cancers. Taking this into consideration with the exercise evidence available in regards to prostate cancer, it is unequivocal to use physical activity as a form of prevention and treatment. This chapter explores the evidence available on using exercise to help attenuate prostate cancer and associated side-effects of conventional treatment, specifically ADT.
It has been said that if a man lives long enough he will eventually get prostate cancer. This statement seems to have some truth to it. The strongest risk factor for prostate cancer is older age. Prostate cancer in rare in younger men, and dying from it is unlikely before 50; however, it is the most prevalent cancer in Western men. A man living in the United States has a lifetime risk of about 1 in 6, making it the most frequent male cancer diagnosis. 1, 28 It is also the second leading cause of death among men in the US. 2
Worldwide, depending on geography and population group, there appears to be a wide variance in prostate cancer. African American men in the US have the highest rates and men in Japan and China have the lowest. When men move from countries of low incidence to countries of high incidence they tend to increase their risk. Furthermore, their risk of dying from the disease also increases. 3, 4 Epidemiological data like this help to highlight the importance of environmental or lifestyle factors on prostate cancer incidence and outcomes.
Like most cancers, prostate cancer has many contributing causal factors. Both internal or non-modifiable factors (e.g. age, genetics, family history, race, geography, etc.) and external or modifiable factors (e.g. lifestyle, exercise, diet, environmental pollution etc.) influence prostate cancer incidence, and prognosis. Although we have little control over the internal factors leading to prostate cancer; we do have greater control over the external factors. It is interesting that non-modifiable risk factors like genetics and geography appear to be less important than external factors. 6,7 Lifestyle choices play an important role in determining “if and when” a man may get prostate cancer. Not only can healthy habits help to decrease the incidence of prostate cancer, they also appear to help in the treatment too.
Lifestyle modification, specifically diet and exercise, are powerful tools in prevention, and both have great potential in assisting with prostate cancer treatment. If prescribed appropriately based on the unique needs of the patient, diet and exercise give a sense of control over their treatment, and appear to improve outcomes in all chronic disease including prostate cancer.
As a example, research shows nutrition and exercise are potent interventions for preventing and treating obesity. And, the evidence clearly shows that being obese increases the risk of all cancers. It is estimated that 1/3 or more of all cancer deaths that occur in the United States each year can be attributed to poor diet and exercise habits. For prostate cancer specifically, data indicates that obesity increases the aggressiveness of prostate cancer, and thus mortality. 8, 9, 10
Of the two (nutrition and exercise) exercise appears to have the most potential in counteracting the negative side-effects of conventional cancer treatment by positively affecting the body in numerous ways. It also has substantial evidence showing positive influences, both in prevention and as adjunctive treatment on other cancers, not to mention most other diseases. For reducing prostate cancer risk, the influence of exercise is promising. 11,12,13 Also, using exercise as way to counteract the negative side effects of conventional prostate cancer treatment can be of great help in improving quality of life and treatment outcomes.
Although, nothing specific on how to prescribe exercise in terms of duration and dose can be definitively fleshed out from the current base of exercise studies in relation to prostate cancer, current evidence does suggest exercise is an extremely important part of treatment strategies. Also, general exercise recommendations for the prostate cancer patient may not meet their unique needs, in terms of fitness level, type of exercise, mind-set, injuries, and even duration, and as such can compromise consistency and sustainability. The aim of this chapter is to elucidate what we know about the impact of exercise in relation to prostate cancer, and to help provide guidelines in recommending exercise to the prostate cancer patients.
What is ADT therapy and the potential side-effects?
Androgen Deprivation Therapy (ADT), also known as androgen suppression therapy, is utilized in conventional treatment either alone or combined with surgery and/or radiation with some prostate cancer patients. ADT suppresses the growth of prostate cancer by starving it of androgens [e.g.(testosterone, dihydrotestosterone [DHT], and immediate androgen precursors, dehydroepiandrosterone [DHEA], dehydroepiandrosterone sulfate [DHEAS], and androstenedione)]. The cancer partly relies on androgens, especially DHT, to grow and spread. In other words, the goal of the ADT is to suppress endogenous androgen production in order to slow down the progression of the cancer and to shrink the tumor.
ADT can be administer either by one or all of the following ways: Orchiectomy (surgical castration), Luteinizing hormone-releasing hormone (LHRH) analogs medications, Anti-androgens medications, and drugs that suppress androgen production. See the Table 1 below for types of ADT.
Unfortunately, ADT is not considered a curative treatment by itself; and, as a result of depriving a man of androgens, ADT can have numerous negative side-effects, some of which can be serious. Furthermore, ADT medication may carry negative side-effects not related to the mechanism of action of depleting androgens, like digestive complaints, increased blood pressure, fluid build-up, seizures, etcetera. Observational studies even suggest that ADT may even cause chronic diseases like cardiovascular disease, diabetes, and osteoporosis. 41
ADT side-effects can affect men both physically and mentally as shown below.
Adverse effects of ADT may include the following: 14
- decreases in psychological well-being (e.g. depression, anxiety, irritability, and anger);
- deficits in attention, memory, and visual processing;
- decreases in bone mineral density;
- metabolic changes such as weight gain, decreased muscle mass, and increased insulin resistance;
- decreased libido and sexual dysfunction;
- shrinkage of penis and testicles;
- hot flashes;
- gynecomastia and breast tenderness;
- reduced testicle size;
- loss of hair;
- increased cholesterol levels;
- and fatigue.
Does exercise improve prostate cancer outcomes?
Current evidence suggests that exercise will reduce the risk of prostate cancer incidence, and this is most apparent with advanced prostate cancer. 14, 15 Physical activity decreases the risk of most chronic disease including heart disease, osteoporosis, diabetes, 18,19, 20 and many cancers. 5, 16, 17, 22, 38 This risk reduction, for a few diseases seems independent of weight reduction. Active men do appear to have decreased risk of prostate cancer. They also tend to have healthier BMIs (Body Mass Indexes) compared to their sedentary peers. Also, weight gain is positively correlated with chronic disease incidence. This makes sense since a high BMI is associated with numerous inflammatory markers, which are associated with chronic diseases like cancer. 46
For prostate cancer the association is a little less clear, although not without evidence. 42, 43 A meta-analysis that combined results from 19 cohort studies and 24 case-control studies indicated that regular physical activity was associated with a modestly reduced risk of prostate cancer. 21 This study confirms the findings in a 2004 review study on exercise and prostate cancer. 23 It is known that obesity seems to increase the risk of aggressive forms of prostate cancer, and thus mortality. 43
Furthermore, as stated by Friedenreich and Thune in their 2001 review, “At least four plausible mechanisms exist that might explain how activity influences prostate cancer risk. These mechanisms include alterations in endogenous hormones, energy balance, immune function, and antioxidant defense mechanisms. Men who are physically active may have lower endogenous androgen levels, decreased body fat, enhanced immune function, and better antioxidant defense mechanisms than inactive men.” 24
One the main theories of why physical activity decreases risk and improves cancer outcomes is because of it’s effect on improving insulin sensitivity and inflammatory markers. Insulin is a growth promoting hormone, and thus can significantly increase cancer risk when levels are chronically high as they are in metabolic syndrome. Also, chronic high level of inflammatory markers such as IL-6, TNF-Î±, and VEGF increase prostate cancer risk. Regularly exercising your muscles acts as a way to get rid of excess of blood sugar, which overtime lowers insulin levels. It also helps lower to inflammation in the body. There does appear to be a positive association between insulin levels, inflammation and prostate cancer risk. 44, 45, 47
Overview of potential pathways linking metabolic disruption to prostate cancer progression. Arrows: stimulates/up regulates. Dashed lines: inhibits/down regulates. Abbreviations: T2DM type 2 diabetes mellitus, IGF insulin-like growth factor, IGFBP IGF binding protein, IL-6 interleukin-6, TNF-Î± tumor necrosis factor alpha, VEGF vascular endothelial growth factor.
Used with permission and printed as published in the International Journal of Molecular Epidemiology and Genetics.
Decreasing the risk of prostate cancer through exercise does not necessarily mean it can be used to improve survival once prostate cancer is diagnosed. Research in this area is also somewhat limited, but shows tremendous promise. There is little doubt that exercise improves the well-being of the cancer patient in a multiple ways. It helps to mitigate many of the side-effects of prostate cancer treatment. Utilized as adjunctive treatment for prostate cancer, exercise has at the very least the potential to improve many of the known side effects of ADT. And like ADT, exercise has the potential to improve disease control and survival outcomes, but without the negative side-effects. Interestingly, a mechanistic model of prostate cancer did show that exercise is associated with increased tumor vascularization and reduced incidence of metastasis. 116
Cancer incidence is continuing to increase primarily due to an aging population. Also, survival rates for most cancers after diagnosis are increasing mostly due to better detection and treatments methods.25 In prostate cancer patients recent data of the relative 10 year survival rate is 99%. 29 This trend can be further potentiated by appropriately disseminating and educating both healthcare providers and cancer patients on the medicinal effects of exercise. Exercise is considered an important tertiary preventive strategy for cancer. 26, 27
The studies specifically addressing prostate cancer and exercise in improving survival rates are limited, but epidemiological studies suggest that regular physical activity does have a positive effect on prostate cancer progression 30 and survival. 31 Clinical randomized controlled studies show that exercise has a beneficial impact on both treatment and disease related side effects. 32-37
Exercise during a man’s life appears to prevent the initiation of a tumor with a lethal potential from ever forming. It is a powerful tool for primary prevention and can potentially eliminate the disease from ever occurring. Furthermore, after a man is diagnosed with prostate cancer, physical activity can positively influence a man’s clinical course in terms of survival and possibly mitigate the negative side-effects from treatment. This makes sense considering that most studies on exercise and cancer and other chronic disease show benefit in both incidence, survival, and quality of life.
Exercise, if prescribed appropriately, is a key component to maintaining a healthy weight, and thus commonsense and logical preventive strategy against, not only prostate cancer, but all chronic disease. Although at this time there is not a clear inverse relationship between prostate cancer incidence and exercise, it does appear prudent to recommend exercise for men as a preventive and adjunctive treatment strategy for prostate cancer.
Does exercise improve the known side effects of ADT?
The short-term effects, both therapeutic and negative, of androgen deprivation therapy (ADT), are well known. On the other hand, the long-term metabolic effects (such as insulin resistance, metabolic syndrome, elevated lipids, cardiovascular disease, low bone mineral density, fat gain, and muscle loss) are only recently being elucidated. 52 The evidence is more clear in regards to ADT and bone mineral density. Within 6-12 months of starting ADT declines in bone mineral density occur, with increased fracture rates within 5 years of treatment.118
The side effects of ADT have the potential to affect men negatively at every level in the body. This treatment deprives the body of androgens. Testosterone, the major male hormone has receptors on every cell in the body, and is the primary androgen the gives the male body his maleness.
Unfortunately, androgens, especially DHT, increase the likelihood that prostate cancer will grow and spread. 39 ADT can halt or slow down prostate cancer, but for only a limited about time, and is therefore not considered a curative treatment. Moreover, the side effects of ADT bring into question the advantages and disadvantages of undergoing this therapy. For some men the side effects are minimal, but for others it ruins their sense of well-being and over-all quality of life.
Exercise utilized as treatment recommendation for prostate cancer will at the very least improve some of the known side effects of ADT. Exercise may even improve disease control and survival outcomes, but without the negative side-effects of ADT. Considering ADT appears to play a role in promoting chronic diseases like osteoporosis, diabetes, and cardiovascular disease, and that exercise appears to not only prevent, but also help to treat these diseases, then common sense dictates that physical activity can also help allay these negative outcomes while undergoing ADT. The research is replete with evidence supporting the use of exercise as a primary intervention for the diseases of osteopenia and osteoporosis, diabetes, and cardiovascular disease. All of these disease states may be side-effects of ADT based on observational studies or exacerbated by ADT.
Another side-effect of ADT is weight gain and a loss of lean tissue. The evidence supports physical activity in any form can help mitigate, reverse, or at least slow down the process in both. Resistance training is especially good for helping to maintain muscle mass, while plyometrics and aerobic exercise appear to be best fortifying bone and improving cardiovascular health, respectively.
Other side-effects of ADT that may be helped by exercise are fatigue, low libido,51 erectile dysfunction,50, 51 elevated cholesterol levels, depression, and anxiety. 49
It is known that exercise has positive impact on depression, anxiety, fatigue, sexual dysfunction, etcetera, when ADT is not cause. Therefore, logical dictates it will help those complaints when ADT is actually the cause. Also, any side-effects of exercise if prescribed appropriately tend to be positive, and are thus unlikely to cause any negative effects.
Why should men going through ADT exercise?
By reducing levels of insulin and/or androgens, physical activity may plausibly reduce prostate cancer risk. Physical activity also enhances immune function and antioxidant defense mechanisms, which could potentially reduce prostate cancer risk. 71
The evidence is overwhelming that complaints of fatigue, depression, anxiety, sexual dysfunction, fat gain, and loss of lean mass are improved with exercise in population groups without prostate cancer or ADT. When ADT is a causative factor of these complaints, studies show that exercise helps to mitigate them. Also, exercise research shows that diseases states like cardiovascular disease, osteoporosis, and diabetes are best treated when exercise is an adjunctive therapy, and in most cases should be the primary intervention.
Exercise is a modifiable factor that patients have complete control over. It gives them a sense of taking part in their treatment. Doctors and other healthcare professionals should promote physical activity as a potent addition to ADT. It is easy to utilize and can be uniquely tailored to the fitness level of the patient. Evidence also indicates that any amount of exercise can help as long as it is done on a regular basis.
One of the main side effects of ADT is fat gain and loss of lean muscle. As fat accumulates on the body, hormones levels become dysregulated and markers of inflammation rise. Loss of lean muscle makes it more difficult to lose weight and can adversely affect immune system function. Excess fat and loss of lean muscle are associated with higher levels insulin, lower levels of testosterone and adiponectin, and higher levels of inflammatory markers, all of which are potential factors in prostate cancer progression.53-56 Exercise especially from a prevention perspective is associated with a positive change in all these biomarkers, and even more so when weight loss occurs.
Waist circumference and Waist to Hip Ratio are positively associated with diagnosis of more advanced prostate cancer. 69,70 Worse prostate cancer outcomes are associated with obesity in adulthood. Obese men tend to develop advanced prostate cancer and have higher rates of recurrence and mortality after diagnosis compared to their height weight proportionate peers. Being overweight with high insulin levels appears to be particularly ominous by being associated with higher rates of prostate cancer mortality.53
A meta-analysis of six cohort studies of initially cancer-free men showed a significant increase in the risk of fatal prostate cancer for each 5 kg/m2 increase in BMI. This study also showed an association of a 20% increased risk of mortality with a 5/kg/m2 increase in BMI in men that already had prostate cancer. 57
Being overweight or obese puts a tremendous amount of metabolic stress on the body. Extra body weight tends to be associated with high levels of insulin, insulin-like growth factor (IGF) and inflammatory compounds, all of which can that increase the risk prostate cancer as well as other chronic diseases. Two recent reports from prospective studies found that high circulating levels of insulin-like growth factor-I and low levels of IGFBP-3 may be associated with aggressive prostate cancer suggesting that insulin-like growth factor-I acts as a tumor promoter. Exercise and being physically active has consistently been show to positively modify insulin and testosterone levels and inflammatory markers in the body.58,59 The biological effects of physical activity, including reduced levels of insulin, androgens, and other growth factors, 67,68 have led to investigations of a possible link with prostate cancer. This beneficial change in the body’s hormonal environment from physical activity also has as a positive on prostate cancer outcomes and incidence.
Insulin has mitogenic and antiapoptotic activity and may exert these properties directly on prostate epithelial cells.72 In addition, hyperinsulinemia may affect prostate cancer risk by increasing levels of free (bioactive) insulin-like growth factor-I or testosterone. 73
As a man ages, he also tends to put on fat, both of which cause levels of testosterone to decrease relative to estrogen. This relative increase in estrogen may play a negative role in prostate carcinogenosis. Also, DHT levels tend to remain high in the prostate as a man ages. This combination of high DHT levels in prostate and higher relative levels of estrogen appear to be negative. Estrogens alone, or in synergism with an androgen, appear to be potent inducers of aberrant growth and neoplastic transformation in the prostate. 60,61
High DHT levels in the prostate as opposed to testosterone are particularly problematic when it comes to prostate cancer. 62 And exercise will increase levels of both DHT and testosterone, but not necessarily in the prostate gland. Obese men tend to have higher levels of estrogen 63,64 and exercise will help to reduce fat gain, and possibly reduce estrogen levels. Nevertheless, exercise can help restore hormonal imbalance to more youthful levels thus possibly attenuating the negative effects of higher relative estrogen levels on the prostate.
What kind of exercise should they do based on the research?
The beneficial web-like effects of exercise as medicine make it a common sense recommendation prostate cancer patient. Furthermore, given that heart disease is the leading cause of death among men with PCa, the clear cardiovascular benefits associated with exercise should be sufficient to recommend this lifestyle intervention to patients.115 The recommendation should be based on the unique needs to the individual by considering the following:
- injuries or pain that may hinder consistency
- fitness level of the patient
- types of physical activity most enjoyed or disliked
- identifying any mental emotional obstacles to exercise
- access to an exercise facility or not
- interest in one-on-one personal training or home exercise programs
- the need for bench-marks in goal oriented individuals
- the need for constant education on the benefits of exercise
- flexibility of exercise programs in order to maintain consistency.
Based on the research the best kind of exercise is one that the patient will do consistently. If consistency is there then the exercise will benefit patient. This does not mean that it is optimal though for helping the prostate cancer patient. The second factor that makes a good exercise program is one that does not stress the body too much to hinder recovery, but just enough to stress the body so that during recovery the body is moved more towards optimal health. Finding the “goldi-locks” point for the individual is key. This means that for the patient, the exercise session can be used as a sort of bio feed back tool. If there is a boost in sense of well-being or accomplishment than that is a good indication the exercise is matched appropriately to the individual needs. Exercise that is not matched to the fitness level of the pt. is exercise that is not sustainable. This usually involves exercise that is to intense or causes excessive body soreness. It can also mean exercise that is boring or not challenging.
Overall, the most important thing is finding activity that is sustainable and not perceived as just another added stressor on the body. For many people this can be as simple as walking everyday. Regular walking does lower inflammatory and hemostatic markers (e.g. von Willebrand factor antigen, fibrinogen, IL-6, receptor antagonist (IL-1ra), and TNF-alpha), all which can negatively impact chronic disease.85 For others it may be a home-based workout. Any yet others may do best with a personal trainer. As healthcare providers, prescribing one size fits all program do not work for most.
For men at risk for prostate cancer, studies have found that even leisure time or recreational physical activity can reduce the risk of aggressive or advanced prostate cancer.15, 75 Also, there are also some clinical pearls for the prostate cancer patient that can be gleaned from the research in terms of what is best for maintaining muscle mass, losing excess fat, and even specifics that may be useful for off-setting the negative effects of ADT.
The best way to preserve muscle with physical activity is utilizing progressive resistance training. This is especially important in an aging population, and even more so when undergoing ADT. As men get older there tends to be a relative gain in fat and loss in muscle. This is in part due to decreasing levels of testosterone and HGH (both of which help maintain muscle mass) and increasing insulin levels, which is primarily a fat storing hormone. Furthermore, as fat accumulates so do the relative levels of estrogens, especially estrone. Both high insulin and relative estrogen levels are also associated with an increase risk prostate cancer.
Resistance training will increase testosterone levels in both young 77 and older men. A study done by Sato K, et al. showed that progressive resistance training of legs for 12 weeks using knee extension and flexion exercises restores age-related declines in levels of sex steroid hormones and steroidogenic enzymes. 74 Many studies on resistance training show more benefit when big muscle groups like legs are exercised as opposed to exercises that isolates certain muscles, like a dumbbell curl for biceps. By incorporated exercises that work many muscle groups at once the beneficial metabolic effects can be magnified. This may also help to reduce the time spent during a workout, which is the number one factor why most people do not exercise.
Resistance exercise relative aerobic exercise helps to preserve muscle, and as such can give one a fat loss advantage. And, any loss of fat will reduce prostate cancer risk and improve outcomes. At the cellular level exercise, can lead to a decrease in the enzyme aromatase, which potentially will lower estrogen levels, like estrone which is produced from fat cells, while also raising testosterone levels. 76
In addition, vigorous or short-duration exercise appears to have a fat-loss and anabolic advantage over moderate intensity long-duration exercise. There is also evidence that this type of exercise is beneficial in reducing the risk of advanced forms of prostate cancer. Vigorous activity is associated with lower levels of insulin, bio-available insulin-like growth factor 1 (IGF1), and inflammatory cytokines, leading to a hormonal mix that may inhibit proliferation and promote apoptosis of prostate cancer cells. 78-82
Among 2705 men with prostate cancer in the Health Professionals Follow-up Study, those who exercised vigorously for 3 or more hours per week had a 61% lower risk of prostate cancer-specific mortality than those with less than 1 hour per week of vigorous activity. 83
A study of prostate cancer progression, including a composite endpoint of biochemical recurrence, secondary treatments, bone metastasis, or cancer death, found that vigorous or brisk walking was associated with a lower risk of recurrence for brisk walking 3 h per week versus easy walking for <3h per week. This study also hinted that vigorous physical exercise was also associated with lower risk of occurrence. Men who walked briskly after diagnosis experienced a 48% reduction in all-cause mortality and a non “statistically significant reduction in prostate cancer“specific mortality compared to men who walked at an easy pace. 84 Based on these findings and the potential biologic mechanisms, it appears that vigorous activity and brisk walking after diagnosis inhibits prostate cancer progression. The authors of another study, Kenfield S. et al., also hypothesized that both vigorous activity and brisk walking after diagnosis would inhibit prostate cancer progression among men diagnosed with localized disease.83
Based on the current evidence any type of exercise can be of benefit for the prostate cancer patient and anyone at risk for any chronic disease. The most important factor for an exercise recommendation is making sure that obstacles to consistency are addressed. After this, specifics on the types of exercise that meet the unique needs of the individual prostate cancer should be determined. Finally, optimizing physical activity for the best therapeutic effect, based on the on-going evidence in prostate cancer and exercise research should be incorporated.
How should it be Rx?
The preponderance of evidence shows that exercise in almost any form can have a positive impact on disease risk and outcomes. There is little reason that it should not be recommended to every prostate cancer patient. A couple caveats to be aware of for the clinician is prescribing it in a way that is matched to the fitness level and lifestyle of the patient. Physical activity that is too intense or even too long in duration compromises consistency and sustainability.
Physical activity is a powerful medicine if the type of activity, dose, duration, and intensity meets the fitness level and psycho-emotional needs of the patient. Careful consideration is needed for each patient, because the “one size fits all” approach has a negative impact on consistency and sustainability, and also sets up the patient for failure. It is also, imperative that exercise is not seen as just another added stressor, or another thing to put on a patient’s to do list. Physical activity should be incorporated into the patient’s unique life in a way that is flexible and thus more likely to become a life-long habit
Physical activity should be uplifting and energizing, while also giving the patient a sense of accomplishment and control over their treatment. For the prostate cancer patient undergoing ADT this is especially true, considering the negative impact ADT can have on the body. Furthermore, the exercise recommendations should be adjusted based on the condition of the patient. This can be easily done by simply asking about it at every visit.
A simple questions to ask during follow-up visits should include:
- Does the exercise energize you or fatigue you after the workout?
- Does it give you a sense of accomplishment?
- Do you think you can be consistent with it?
- Is it enjoyable or just another added stressor in your life?
- Does the activity you are doing aggravate any joint pain or body aches?
- Is it sustainable in the long-term based on your lifestyle?
- Do you believe the activity will help you with your health?
In general, for most people, the foundation of an exercise program that provides the most health benefit should be walking at least 30 minutes/day for most days of the week. Walking at a brisk or vigorous pace gives even more health benefit.100 A brisk pace is defined to be somewhere between 3.5 mph – 4.4 mph ( 17 min/mile to 13 min/mile) with fitter people being able to sustain the upper range. Walking at a pace between of 4.3 mph and 5.5 mph is consider power walking, and for most people is not sustainable in the long-term. The key here is that any walking even if it is under 3.0 mph will impart benefit if it can be done consistently; however, the optimal range for health benefit is brisk walking, but only if it the answers to the above questions 1-7 are positive.
Another interesting aspect of the health benefits of walking may be the environment that you do it in. Walking in nature or a more scenic environment seems to be much better for mental emotional well-being than a more urban environment.86, 87 Walking in wooded areas or parks within urban environments certainly suffice in giving this added health benefit. 88,89 Another name for this type of walking therapy is “forest bathing,” known in Japan as Shinrin-yoku.
A combination of resistance and aerobic exercise appear to give the greatest benefit in terms of fat loss and cardiovascular fitness. Ho SS, et al. showed a combination of 15 minutes of aerobic exercise and 15 minutes of resistance exercise is superior to either 30 min of aerobic exercise or 30 min of resistance exercise. 90 Signal RJ, et al. also showed a slight fat loss advantage in combined exercise regimen of aerobic and resistance training on obese adolescents. 91 And, Sanal E, et al. showed the same fat loss advantage of combined training in both obese males and females. 92 And in older men, Sousa N, et al. showed there was a fat loss advantage and cardiovascular benefit in the combined aerobic and resistance training group over aerobic alone. 93
What about the intensity of workout? Does greater intensity impart greater health benefit according to the research? In general the answer to this appears to be yes, but more research is needed. Most research focuses on high intensity interval training which is defined as alternating periods of short intense anaerobic activity with less-intense recovery periods. These types of workouts appear to have a better cardiovascular benefit and fat burning advantage over moderate intensity continuous exercise, like jogging. 94 Vigorous short-duration exercise can give one better results aerobic fitness results in a shorter amount of time, but for most people it is not sustainable in the long-run, and has low adherence rates. However, the best workout for any individual is the one that they will do, and one they have the ability to do.
The exercise studies on prostate cancer patients appear to be to show a greater benefit with exercise programs that combine resistance and aerobic exercise. 98 It also appears that more vigorous or intensity exercise protocols impart greater benefit by lowering prostate cancer specific mortality. 31 A Cochrane review by Mishra SI, et al. showed positive effects of exercise interventions are more pronounced with moderate- or vigorous-intensity versus mild-intensity exercise programs. 101 Also, higher intensity exercise post-diagnosis appears to be associated with a reduced risk of prostate cancer mortality.83 Considering the side effects of ADT (i.e. sarcopenia, loss of bone mass, and reduced muscle strength) resistance training is a vital component for men undergoing ADT, and may lead to higher adherence rates than other forms of exercise. 96, 97, 99 Adherence rates are also increased significantly with supervised exercise programs.
Park SW, et. all showed that combining resistance training with Kegel exercise after patients under going a radical prostatectomy gave greater improvements in physical function and quality of life and continence rates than doing Kegel exercises alone. 95 Kegel exercises, if done correctly, can be of great benefit for anyone with sexual dysfunction and urinary incontinence. It may also help to prevent these issues. The other great thing about Kegel exercises is that they can be done anywhere or anytime, and do not require and equipment, like a resistance or cardiovascular workout does.
Benefits of Kegel exercises for men include:
- Strengthens and isolates the Pubococcygeus Muscles (Refer to Figure 2 to see where these muscles are located.)
- Increases blood flow and nerve supply to the pelvic region
- Assists in attaining and maintaining an erection
- Helps prevent and treat urinary incontinence, and may even improve overall urinary tract health
To learn how to do Kegels try the following:
- During urination, try to stop or at least slow down the flow of urine. If you can do this then you have successful isolated the pubococcygeus muscles.
- Try not to tense the muscles in legs, abdomen or buttocks, and try not to hold your breath.
General recommendations for doing Kegels are the following:
- Contract the pubococcygeus muscles to a count of 5 -10 seconds and release the muscle to a count of 5 -10 seconds.
- Can be done sitting, standing, or lying down.
- Do at least 1 set of 10, 3 – 5 times per day everyday
Possible Exercise Contraindications
Knowing that almost any type of exercise will give the body some benefit does not necessarily mean it will give benefit to the unique health needs of the prostate cancer patient. An example of a possible exercise contraindication for any man with a compromised prostate is prolonged bicycling. Not only does this form of exercise put a pressure on the perineal area, it also is not great for preventing bone loss.
Bicycling is one of the major risk factors for erectile dysfunction in healthy men, with incidence of 13-24%. 102 This is due to the prolonged compression of perineal arteries leading to reduced chronic penile perfusion. The most common bicycling associated urogenital problems are nerve entrapment syndromes presenting as genitalia numbness.104 Other less common symptoms include priapism, penile thrombosis, infertility, hematuria, torsion of spermatic cord, prostatitis, perineal nodular induration and elevated serum PSA.103
It is known that ADT can accelerate bone loss, and as such, physical activity that may further potentiate bone loss or do nothing to prevent it should be minimized if possible. This includes any activities that reduce the gravitational load on the body like, swimming or cycling, and any exercise that is too repetitive in nature, like prolonged jogging.105 Swimming mimics the anti-gravitational environment of the astronaut while prolonged repetitive exercises cause your mechano-receptors in the bone to ignore the stimulus.
Exercise and Improving Sexual Performance
Exercise can improve sexual function simply through it’s beneficial effect on sense of well-being in the short-term. Consistent exercise will also help to lower blood lipids, insulin and blood sugar, and balance hormones, while improving overall cardiovascular health and, all of which have positive impacts on erectile dysfunction and libido. Being overweight or obese is a common cause of sexual dysfunction due to its destructive effects on cardiovascular health. Physical activity will assist one in losing excess fat weight, which not only enhances a sense of well-being, but also may help reverse erectile dysfunction.106 Specific exercises the increase blood flow to the perineal area, like Kegel exercises, are extremely helpful. Any exercises that improve core strength are also helpful for improving sexual performance. These include but are not limited to push-ups, squats, lunges, hip thrusts. See Figures 3-5
Another form of exercise that may enhance sexual performance in men is yoga.107, 108 Yoga helps to strengthen core muscles while also improve flexibility. It also is extremely effective for reducing anxiety and depression, thus imparting a greater sense of well-being. Practicing yoga has been shown to lower stress hormones 111-113 (e.g. cortisol and epinephrine) and increase melatonin levels.114 Strengthening core muscles and helping to lower stress hormone are useful for mitigating symptoms of sexual dysfunction. And, increasing melatonin appears to have anti-cancer effects for all types of cancer including prostate.109,110
Some yoga poses may help to improve blood flow and tone to the prostate area, like Yoga Mudra, Locust, and Moola (Mula) Bandha.108, 118 See Figure 6 below. Detailed descriptions of Mula Bandha can be found on the internet.118
The evidence for yoga reducing anxiety and depression, while increasing general-well being is fairly substantial. Improving well-being can have a dramatic beneficial effect on sexual function. More data is needed for a direct positive effect on prostate cancer and erectile dysfunction.
Examples of a program?
Again, the most important aspect of implementing any exercise program for the both the clinician and person doing it is figuring out how likely it will be done consistently. If the exercise program is too intense or too difficult than it’s consistency will be compromised. The same is true if the prescribed exercise program does not take into account the persons unique needs (i.e. any injuries, access to gym, neighborhood insecurities, etc.)
The following figures 3-5 give general guidelines for a daily exercise program. The foundation of any exercise program is walking for most people (See Figure 3). This should be done everyday for a minimum of 30 mins per day. The figures below (4-6) give optimal guidelines; but care should be taken to acclimate into any exercise program. In other words, doing something is better than doing nothing, and doing less is better than doing more, especially if there is a chance for compromising the consistency of daily physical activity.
Figure 3 (The Home Based Workout without any Equipment)
This workout is great for anyone that needs to slowly acclimate into a resistance based workout.
Figure 4 (The Dumbell Based Workout)
Figure 5 (The Gym Based Workout)
Figure 6 (Yoga Postures)
- Howlander N, et al., SEER Cancer Statistics Review 1975â€“2008, National Cancer Institute. Bethesda, MD, http://www.seer.cancer.gov/csr/1975_2008/, based on November 2010 SEER data submission, posted to the SEER web site, 2011)
- American Cancer Society – Key Statistics About Prostate Cancer. [(accessed on 18 Feb 2015)]. Available online: http://www.cancer.org/cancer/prostatecancer/detailedguide/prostate-cancer-key-statistics
- Shimizu H, et al. Cancers of the prostate and breast among Japanese and white immigrants in Los Angeles County. Br J Cancer. 1991;63:963â€“6.
- Yu H, et al. Comparative epidemiology of cancers of the colon, rectum, prostate and breast in Shanghai, China versus the United States. Int J Epidemiol. 1991;20:76â€“81.
- World Cancer Research Fund/American Institute for Cancer Research. Food, Nutrition, Physical Activity, and the Prevention of Cancer: A Global Perspective. Washington, DC: World Cancer Research Fund/American Institute for Cancer Research; 2007.
- Czene K, Lichtenstein P, Hemminki K. Environmental and heritable causes of cancer among 9.6 million individuals in the Swedish Family-Cancer Database. Int J Cancer. 2002; 99: 260-266.
- Willett WC. Balancing life-style and genomics research for disease prevention. Science. 2002; 296: 695-698.
- Amling CL, Riffenburgh RH, Sun L, et al. Pathologic variables and recurrence rates as related to obesity and race in men with prostate cancer undergoing radical prostatectomy. J Clin Oncol. 2004; 22: 439-445.
- Freedland SJ, Aronson WJ, Kane CJ, et al. Impact of obesity on biochemical control after radical prostatectomy for clinically localized prostate cancer: a report by the Shared Equal Access Regional Cancer Hospital database study group. J Clin Oncol. 2004; 22: 446-453.
- Cao Y, Ma J. Body mass index, prostate cancer-specific mortality, and biochemical recurrence: a systematic review and meta-analysis. Cancer Prev Res (Phila). 2011; 4: 486-501.
- Liu Y, Hu F, Li D, et al. Does physical activity reduce the risk of prostate cancer? A systematic review and meta-analysis. Eur Urol. 2011; 60: 1029-1044.
- Giovannucci EL, Liu Y, Leitzmann MF, Stampfer MJ, Willett WC. A prospective study of physical activity and incident and fatal prostate cancer. Arch Intern Med. 2005; 165: 1005-1010.
- Vainio H, Kaaks R, Bianchini F. Weight control and physical activity in cancer prevention: international evaluation of the evidence. Eur J Cancer Prev. 2002; 11( suppl 2): S94-S100.
- American Cancer Society – Hormone (androgen deprivation) therapy for prostate cancer. [(accessed on 19 Feb 2015)]. Available online: http://www.cancer.org/cancer/prostatecancer/detailedguide/prostate-cancer-treating-hormone-therapy
- Giovannucci EL, Liu Y, Leitzmann MF, Stampfer MJ, Willett WC. A prospective study of physical activity and incident and fatal prostate cancer. Arch Intern Med. 2005; 165: 1005-1010.
- Patel AV, Rodriguez C, Bernstein L, Chao A, Thun MJ, Calle EE. Obesity, recreational physical activity, and risk of pancreatic cancer in a large U.S. cohort. Cancer Epidemiol Biomarkers Prev. 2005; 14: 459-466.
- Patel AV, et al. Recreational physical activity and risk of postmenopausal breast cancer in a large cohort of US women. Cancer Causes Control. 2003; 14: 519-529.
- Sallis JF, Glanz K. Physical activity and food environments: solutions to the obesity epidemic. Milbank Q. 2009; 87: 123-154.
- Colberg SR, Sigal RJ, Fernhall B, et al. Exercise and type 2 diabetes: the American College of Sports Medicine and the American Diabetes Association: joint position statement. Diabetes Care. 2010; 33: e147-e167.
- Booth FW, et al., Lack of exercise is a major cause of chronic diseases. Compr Physiol. 2012 Apr;2(2):1143-211.
- Liu Y, Hu F, Li D, et al. Does physical activity reduce the risk of prostate cancer? A systematic review and meta-analysis. Eur Urol. 2011; 60: 1029-1044.
- HÃ¥llmarker U, et al. Cancer incidence in participants in a long-distance ski race (Vasaloppet, Sweden) compared to the background population. Eur J Cancer. 2015 Feb 7. pii: S0959-8049(14)01169-1.
- Torti DC, Matheson GO., Exercise and prostate cancer. Sports Med. 2004;34(6):363-9.
- Friedenreich CM, Thune I. A review of physical activity and prostate cancer risk. Cancer Causes Control 2001;12:461â€“75.
- Ferlay J. et al. GLOBO-CAN 2008: Cancer Incidence and Mortality Worldwide. [(accessed on 9 May 2014)]. Available online: http://www.iarc.fr/en/media-centre/iarcnews/2010/globocan2008.php.
- Demark-Wahnefried W. Cancer survival: Time to get moving? Data accumulate suggesting a link between physical activity and cancer survival. J. Clin. Oncol. 2006;24:3517â€“3518. doi: 10.1200/JCO.2006.06.6548.
- Lynch B.M., Dunstan D.W., Vallance J.K., Owen N. Don’t take cancer sitting down: A new survivorship research agenda. Cancer. 2013;119:1928â€“1935.
- Siegel R, et al. Cancer treatment and survivorship statistics, 2012. Ca-A Cancer J. Clin. 2012;62:220â€“241. doi: 10.3322/caac.21149.
- American Cancer Society Survival Rates for Prostate Cancer. [(accessed on 18 Feb 2015)]. Available online: http://www.cancer.org/cancer/prostatecancer/detailedguide/prostate-cancer-survival-rates.
- Richman E.L., Kenfield S.A., Stampfer M.J., Paciorek A., Carroll P.R., Chan J.M. Physical activity after diagnosis and risk of prostate cancer progression: data from the cancer of the prostate strategic urologic research endeavor. Cancer Res. 2011;71:3889â€“3895. doi: 10.1158/0008-5472.CAN-10-3932.
- Kenfield S.A., Stampfer M.J., Giovannucci E., Chan J.M. Physical activity and survival after prostate cancer diagnosis in the health professionals follow-up study. J. Clin. Oncol. 2011;29:726â€“732. doi: 10.1200/JCO.2010.31.5226.
- Wolin K.Y., Luly J., Sutcliffe S., Andriole G.L., Kibel A.S. Risk of urinary incontinence following prostatectomy: The role of physical activity and obesity. J. Urol. 2010;183:629â€“633.
- Galvao D.A., Taaffe D.R., Spry N., Joseph D., Newton R.U. Combined resistance and aerobic exercise program reverses muscle loss in men undergoing androgen suppression therapy for prostate cancer without bone metastases: a randomized controlled trial. J. Clin. Oncol. 2010;28:340â€“347. doi: 10.1200/JCO.2009.23.2488.
- Cramp F, Byron-Daniel J. Exercise for the management of cancer-related fatigue in adults. Cochrane Database Syst Rev. 2012;14(11):CD006145.
- Storer TW, Miciek R, Travison TG. Muscle function, physical performance and body composition changes in men with prostate cancer undergoing androgen deprivation therapy. Asian J Androl. 2012;14(2):204â€“221. doi: 10.1038/aja.2011.104.
- Centemero A, Rigatti L, Giraudo D, Lazzeri M, Lughezzani G, Zugna D, Montorsi F, Rigatti P, Guazzoni G. Preoperative pelvic floor muscle exercise for early continence after radical prostatectomy: a randomised controlled study. Eur Urol. 2010;57(6):1039â€“1043. doi: 10.1016/j.eururo.2010.02.028.
- Mustian KM, et al. A 4-week home-based aerobic and resistance exercise program during radiation therapy: a pilot randomized clinical trial. J Support Oncol. 2009 Sep-Oct;7(5):158-67.
- Oliveria SA and Lee IM. Is exercise beneficial in the prevention of prostate cancer? Sports Med. 1997 May;23(5):271-8.
- Pandini G, Mineo R, Frasca F, Roberts CT Jr, Marcelli M, Vigneri R, Belfiore A (March 2005). “Androgens up-regulate the insulin-like growth factor-I receptor in prostate cancer cells”. Cancer Res. 65 (5): 1849â€“57.
- Choi SM and Kam SC. Metabolic effects of androgen deprivation therapy. Korean J Urol. 2015 Jan;56(1):12-18.
- Lomax AJ, et al. “First, do no harm”: Managing the metabolic impacts of androgen deprivation in men with advanced prostate cancer. Intern Med J. 2015 Mar 2. doi: 10.1111/imj.12731.
- Hernandez BY, et al. Relationship of body mass, height, and weight gain to prostate cancer risk in the multiethnic cohort. Cancer Epidemiol Biomarkers Prev. 2009 Sep;18(9):2413-21.
- Zhang X, et al. Impact of obesity upon prostate cancer-associated mortality: A meta-analysis of 17 cohort studies. Oncol Lett. 2015 Mar;9(3):1307-1312.
- Kayali M, et al. The relationship between prostate cancer and presence of metabolic syndrome and late-onset hypogonadism. Urology. 2014 Dec;84(6):1448-52.
- Shiozawa S and Horie S., Prostate cancer and metabolic syndrome. Nihon Rinsho. 2014 Dec;72(12):2234-40.
- Kitahara CM, et al. Body mass index, physical activity, and serum markers of inflammation, immunity, and insulin resistance. Cancer Epidemiol Biomarkers Prev. 2014 Dec;23(12):2840-9.
- Burton AJ, et al. Metabolic imbalance and prostate cancer progression. Int J Mol Epidemiol Genet. 2010; 1(4): 248â€“271.
- SA Oliviera and M Lee. Is exercise beneficial in the prevention of prostate cancer. Sports Med. 1997 May;23(5):271-8.
- Penedo FJ and Dahn JR. Exercise and well-being: a review of mental and physical health benefits associated with physical activity. Curr Opin Psychiatry. 2005 Mar;18(2):189-93.
- LA Vignera S, et al. Physical activity and erectile dysfunction in middle-age men. J Androl. 2012 Mar-Apr;33(2):154-61.
- Cormie P, et al. Exercise maintains sexual activity in men undergoing androgen suppression for prostate cancer: a randomized controlled trial. Prostate Cancer Prostatic Dis. 2013 Jun;16(2):170-5.
- Choi KM and Kam SC. Metabolic effects of androgen deprivation therapy. Korean J Urol. 2015 Jan;56(1):12-8.
- Ma J, Li H, Giovannucci E, Mucci L, Qiu W, et al. Prediagnostic body-mass index, plasma C-peptide concentration, and prostate cancer-specific mortality in men with prostate cancer: a long-term survival analysis. Lancet Oncol. 2008;9:1039â€“47.
- Li H, Stampfer MJ, Mucci L, Rifai N, Qiu W, et al. A 25-year prospective study of plasma adiponectin and leptin concentrations and prostate cancer risk and survival. Clin Chem. 2010;56:34â€“43.
- Platz EA, Giovannucci E. The epidemiology of sex steroid hormones and their signaling and metabolic pathways in the etiology of prostate cancer. J Steroid Biochem Mol Biol. 2004;92:237â€“.
- de Marzo AM, Platz EA, Sutcliffe S, Xu J, GrÃ¶nberg H, et al. Inflammation in prostate carcinogenesis. Nat Rev Cancer. 2007;7:256â€“69.
- Cao Y, Ma J. Body mass index, prostate cancer-specific mortality, and biochemical recurrence: a systematic review and meta-analysis. Cancer Prev Res (Phila) 2011;4:486â€“501.
- Hackney AC. The male reproductive system and endurance exercise. Medicine & Science in Sports & Exercise 1996;28:180â€“9.
- IARC. IARC Handbooks on Cancer Prevention:weight control and physical activity, Vol. 6. Lyon: IARC. 2002.
- Carruba G. Estrogen and prostate cancer: an eclipsed truth in an androgen-dominated scenario. J Cell Biochem. 2007 Nov 1;102(4):899-911.
- Ho SM. Estrogens and anti-estrogens: key mediators of prostate carcinogenesis and new therapeutic candidates. J Cell Biochem. 2004 Feb 15;91(3):491-503.
- Marker PC, Donjacour AA, Dahiya R, et al: Hormonal, cellular, and molecular control of prostatic development. Dev Biol 253:165-174, 2003.
- Zumoff. Hormonal abnormalities in obesity. Acta Med Scand Suppl. 1988;723:153-60.
- Schneider G, et al. Increased estrogen production in obese men. J Clin Endocrinol Metab. 1979 Apr;48(4):633-8.
- Stattin P, Bylund A, Rinaldi S, et.al. Plasma insulin-like growth factor-I, insulin-like growth factor binding proteins, and prostate cancer risk: a prospective study. Journal of the National Cancer Institute 2000;92:1910â€“17.
- Chan JM, Stampfer MJ, Ma J, et.al. Insulin-like growth factor-I (IGF-I) and IGF binding protein-3 as predictors of advanced-stage prostate cancer. Journal of the National Cancer Institute 2002;94:1099â€“106.
- Assah FK, Brage S, Ekelund U, Wareham NJ. The association of intensity and overall level of physical activity energy expenditure with a marker of insulin resistance. Diabetologia. 2008;51:1399â€“407.
- McTiernan A. Mechanisms linking physical activity with cancer. Nat Rev Cancer. 2008;8:205â€“11.
- Pischon T, Boeing H, Weikert S, Allen N, Key T, et al. Body size and risk of prostate cancer in the European prospective investigation into cancer and nutrition. Cancer Epidemiol Biomarkers Prev. 2008;17:3252â€“61.
- MacInnis RJ, English DR, Gertig DM, Hopper JL, Giles GG. Body size and composition and prostate cancer risk. Cancer Epidemiol Biomarkers Prev. 2003;12:1417â€“21.
- Friedenreich CM, Thune I. A review of physical activity and prostate cancer risk. Cancer Causes Control. 2001;12:461â€“75.
- Qian H, Hausman DB, Compton MM, et al. TNFÎ± induces and insulin inhibits caspase 3-dependent adipocyte apoptosis. Biochem Biophys Res Commun. 2001;284:1176â€“83.
- Giovannucci E. Nutrition, insulin, insulin-like growth factors and cancer. Horm Metab Res. 2003;35:694â€“704.
- Sato K, et al. Resistance training restores muscle sex steroid hormone steroidogenesis in older men. FASEB J. 2014 Apr;28(4):1891-7.
- Patel AV, Rodriguez C, Jacobs EJ, Solomon L, Thun MJ, et al. Recreational physical activity and risk of prostate cancer in a large cohort of U.S. men. Cancer Epidemiol Biomarkers Prev. 2005;14:275â€“9.
- HÃ¥konsen LB, et al. Does weight loss improve semen quality and reproductive hormones? Results from a cohort of severely obese men. Reprod Health 2011; 8 (1): 24.
- Marin DP, Figueira AJ Junior, Pinto LG (2006). “One session of resistance training may increase serum testosterone and triiodetironine in young men”. Medicine & Science in Sports & Exercise 38 (5): S285.
- Haverkamp J, Charbonneau B, Ratliff TL. Prostate inflammation and its potential impact on prostate cancer: a current review. J Cell Biochem. 2008 Apr 1;103(5):1344â€“53.
- Lee I, Blair S, Manson J, Paffenbarker RSJ, editors. Epidemiologic Methods in Physical Activity Studies. New York: Oxford University Press; 2009.
- Frasca F, Pandini G, Sciacca L, et al. The role of insulin receptors and IGF-I receptors in cancer and other diseases. Arch Physiol Biochem. 2008 Feb;114(1):23â€“37.
- Barb D, Williams CJ, Neuwirth AK, Mantzoros CS. Adiponectin in relation to malignancies: a review of existing basic research and clinical evidence. Am J Clin Nutr. 2007 Sep;86(3):s858â€“66.
- Barnard RJ, Ngo TH, Leung PS, Aronson WJ, Golding LA. A low-fat diet and/or strenuous exercise alters the IGF axis in vivo and reduces prostate tumor cell growth in vitro. Prostate. 2003 Aug 1;56(3):201â€“6.
- Kenfield SA, Stampfer MJ, Giovannucci E, Chan JM. Physical activity and survival after prostate cancer diagnosis in the health professionals follow-up study. J Clin Oncol. 2011;29:726â€“32.
- Richman EL, Kenfield SA, Stampfer MJ, Paciorek A, Carroll PR, et al. Physical activity after diagnosis and risk of prostate cancer progression: data from the cancer of the prostate strategic urologic research endeavor. Cancer Res. 2011;71:3889â€“95.
- Hamer M, Steptoe A. Walking, vigorous physical activity, and markers of hemostasis and inflammation in healthy men and women. Scand J Med Sci Sports. 2008 Dec;18(6):736â€“41.
- Berman MG, et al. The cognitive benefits of interacting with nature. Psychol Sci. 2008 Dec;19(12):1207-12.
- Song C, et al. Effect of forest walking on autonomic nervous system activity in middle-aged hypertensive individuals: a pilot study. Int J Environ Res Public Health. 2015 Mar 2;12(3):2687-99.
- South EC, et al. Neighborhood Blight, Stress, and Health: A Walking Trial of Urban Greening and Ambulatory Heart Rate. Am J Public Health. 2015 Mar 19:e1-e5.
- Takayama N, et al. Emotional, restorative and vitalizing effects of forest and urban environments at four sites in Japan. Int J Environ Res Public Health. 2014 Jul 15;11(7):7207-30.
- Ho SS, et al. The effect of 12 weeks of aerobic, resistance or combination exercise training on cardiovascular risk factors in the overweight and obese in a randomized trial. BMC Public Health. 2012 Aug 28;12:704.
- Sanal E, et al. Effects of aerobic or combined aerobic resistance exercise on body composition in overweight and obese adults: gender differences. A randomized intervention study.
- Signal RJ, et al. Effects of aerobic or combined aerobic resistance exercise on body composition in overweight and obese adults: gender differences. A randomized intervention study. Eur J Phys Rehabil Med. 2013 Feb;49(1):1-11.
- Sousa N, et al. A randomized 9-month study of blood pressure and body fat responses to aerobic training versus combined aerobic and resistance training in older men. Exp Gerontol. 2013 Aug;48(8):727-33.
- Shiraev T, et al., Evidence based exercise – clinical benefits of high intensity interval training. Aust Fam Physician. 2012 Dec;41(12):960-2.
- Park SW, et al. Recovery of overall exercise ability, quality of life, and continence after 12-week combined exercise intervention in elderly patients who underwent radical prostatectomy: a randomized controlled study. Urology. 2012 Aug;80(2):299-305.
- Winters-Stone KM, et al. Resistance training reduces disability in prostate cancer survivors on androgen deprivation therapy: evidence from a randomized controlled trial. Arch Phys Med Rehabil. 2015 Jan;96(1):7-14.
- Segal RJ, et al. Resistance exercise in men receiving androgen deprivation therapy for prostate cancer. J Clin Oncol. 2003 May 1;21(9):1653-9.
- GalvÃ£o DA, et al. Combined resistance and aerobic exercise program reverses muscle loss in men undergoing androgen suppression therapy for prostate cancer without bone metastases: a randomized controlled trial. J Clin Oncol. 2010 Jan 10;28(2):340-7.
- GalvÃ£o DA, et al. Exercise can prevent and even reverse adverse effects of androgen suppression treatment in men with prostate cancer. Prostate Cancer Prostatic Dis. 2007;10(4):340-6.
- Richman EL, et al. Physical activity after diagnosis and risk of prostate cancer progression: data from the cancer of the prostate strategic urologic research endeavor.Cancer Res. 2011 Jun 1;71(11):3889-95.
- Mishra SI, et al. Exercise interventions on health-related quality of life for people with cancer during active treatment.Cochrane Database Syst Rev. 2012 Aug 15;8:CD008465.
- Gulino G, et al. Sport, infertility and erectile dysfunction. Urologia. 2010 Apr-May;77(2):100-6.
- Leibovitch I, Mor Y. The vicious cycling: bicycling related urogenital disorders. Eur Urol. 2005 Mar;47(3):277-86; discussion 286-7.
- Sommer F, et al. Impotence and genital numbness in cyclists. Int J Sports Med. 2001 Aug;22(6):410-3.
- Scofield KL, Hecht S. Bone health in endurancee athletes: runners, cyclists, and swimmers. Curr Sports Med Rep. 2012 Nov-Dec;11(6):328-34.
- Glina S, et al. Modifying risk factors to prevent and treat erectile dysfunction. J Sex Med. 2013 Jan;10(1):115-9.
- Dhikav V, et al. Yoga in male sexual functioning: a noncompararive pilot study. J Sex Med. 2010 Oct;7(10):3460-6.
- Sengupta P, et al. Male reproductive health and yoga. Int J Yoga. 2013 Jul;6(2):87-95.
- SÃ¡nchez-Hidalgo M, et al. Melatonin, a natural programmed cell death inducer in cancer. Curr Med Chem. 2012; 19(22):3805-21.
- Sohn EJ, et. al. Upregulation of miRNA3195 and miRNA374b Mediates the Anti-Angiogenic Properties of Melatonin in Hypoxic PC-3 Prostate Cancer Cells. J Cancer. 2015 Jan 1;6(1):19-28.
- Vedamurthachar A, et al. Antidepressant efficacy and hormonal effects of Sudarshana Kriya Yoga (SKY) in alcohol dependent individuals. J Affect Disord. 2006 Aug; 94(1-3):249-53.
- Thirthalli J, et al. Cortisol and antidepressant effects of yoga. Indian J Psychiatry. 2013 Jul;55(Suppl 3):S405-8.
- Selvamurthy W, et al. A new physiological approach to control essential hypertension. Indian J Physiol Pharmacol. 1998 Apr; 42(2):205-13.
- Carlson LE, et al. Mindfulness-based stress reduction in relation to quality of life, mood, symptoms of stress, and immune parameters in breast and prostate cancer outpatients. Psychosom Med. 2003 Jul-Aug; 65(4):571-81.
- Allot EH, et al. Obesity and prostate cancer: weighing the evidence. Eur Urol. 2013 May;63(5):800-9.
- Jones LW, et al. Exercise modulation of the host-tumor interaction in an orthotopic model of murine prostate cancer. J Appl Physiol (1985). 2012 Jul; 113(2):263-72.
- Alibhai SM, et al. Long-term side effects of androgen deprivation therapy in men with non-metastatic prostate cancer: a systematic literature review. Crit Rev Oncol Hematol. 2006 Dec;60(3):201-15.