Participants: Don Morgan
Series Code: WM
Program Code: WM000381
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00:01 The following program presents principles
00:03 designed to promote good health 00:04 and is not intended to take the place of 00:06 personalized professional care. 00:07 The opinions and ideas expressed are those 00:10 of the speaker. Viewers are encouraged 00:12 to draw their own conclusions 00:14 about the information presented. 00:37 Hello and welcome to Wonderfully Made, 00:39 are you interested in leading a lifestyle 00:42 that can help in preventing cancer? 00:45 My name is Don Morgan and I'm an exercise 00:48 physiologist and a professor in the 00:51 Department of Health and Human Performance 00:53 at Middle Tennessee State University. 00:56 This is the eight in a series of programs 00:59 describing the many health and fitness 01:01 benefits that result from adopting a 01:03 physically active lifestyle. 01:05 In today's program we're going to discuss 01:09 the role that physical activity 01:11 and exercise can play in improving 01:13 physical function and quality 01:16 of life in cancer survivors. 01:20 The term cancer actually describes over 01:24 100 diseases that can occur in just about 01:27 any body tissue or organ. Normally, 01:31 body cells grow, divide and die in a tightly 01:37 regulated fashion. With cancer however 01:41 there is an uncontrolled growth in spread of 01:45 abnormal cells that can destroy surrounding 01:48 tissues and migrate to other areas of the body. 01:53 Most cancers can be classified into 01:55 one of four categories. Carcinomas, 02:00 which develop from cells that cover glands, 02:02 internal organs and the surface of the body 02:05 account for 80 to 90 percent of all cancers. 02:10 Prostate, colon and breast cancers are 02:14 examples of carcinomas. Leukemia's are cancers 02:19 arising from cells in the blood. 02:21 Lymphomas which involve cells of the 02:24 immune system, and sarcomas which occur in 02:28 connective tissue or other types of cancer. 02:33 Based on information from the American 02:36 Cancer Society, Americans have about 02:40 a 41 percent chance of developing 02:42 some form of invasive cancer during 02:44 their lifetime. According to the Centers 02:48 for Disease Control, cancer was the second 02:51 leading cause of death in the United States 02:53 in 2003 and accounted for 23 percent 02:58 of all deaths. However in the latest report 03:03 from the American Cancer Society more 03:06 American's under the age of 85 actually 03:09 died of cancer rather then heart diseases 03:12 which still remains the leading cause of death 03:15 in the U.S. Interestingly, while the 03:19 very oldest American's continue to die of 03:22 heart diseases more than they do of cancer 03:26 this trend is expected to reverse itself 03:28 by the year 2018. With age the probability of 03:34 developing most cancers increases markedly 03:38 which makes cancer a disease that 03:40 primarily affects older adults. 03:44 However some cancers like Hodgkin's disease, 03:48 non-Hodgkin's lymphoma, leukemia 03:51 and testicular cancer affect mostly 03:55 younger persons. Currently the five year 04:00 relative survival rate for cancer is about 04:02 60 percent although this figure varies 04:06 depending on the type of cancer detected 04:09 and the extent of the diseases 04:12 when it's diagnosed. Given the increase in 04:16 cancer incidents and the increase in 04:19 survival rates fitness professionals can expect 04:22 to serve a growing numbers of 04:24 cancer survivors in the future. 04:28 The following graphic displays risk factors 04:31 for cancer, as shown in this figure many causes 04:35 of cancer are linked to the lifestyle behaviors. 04:39 It is a particular interest to know 04:41 that the combined influence of diet 04:44 and physical inactivity is the single largest 04:47 cancer risk factor. When added in with 04:50 tobacco use as many as 65 percent 04:54 of all cancers may be preventable 04:57 by not smoking, eating a healthy diet, 05:01 performing regular physical activity 05:04 and maintaining a healthy weight. 05:08 In studying the potential relationship 05:10 between physical inactivity in cancer 05:13 it's important to recognize that the link 05:16 between these two factors is not new. 05:20 In a text written over 300 years ago 05:22 it was suggested that physical activity 05:25 might play a role in the expression 05:28 of human cancer. In 1922 Australian 05:33 researchers noted that primitive tribes 05:35 who worked continuously for food displayed 05:39 lower rates of cancer compared to people 05:41 living in more civilized societies. 05:45 In the same year it was also observed that 05:48 most cancer patients led relatively 05:51 inactive lives and that men who worked hard 05:54 were less cancer prone compared to those 05:57 who tended to sit while performing daily work 06:00 activities. Later in the 1970's other scientists 06:06 observed that a lower cancer risk seem to be 06:09 present in former athletes, people 06:12 who were employed in active occupations 06:16 and those who exercised during 06:18 their leisure time. The following graphic 06:22 depicts the relationship between overall 06:24 cancer death rates and fitness status 06:27 in a large cohort of men and woman who have 06:29 studied at the Institute For Aerobics Research 06:32 in Dallas, Texas as shown in this figure 06:37 men and women who displayed good 06:39 fitness levels exhibited much lower age 06:42 adjusted cancer death rates then those with 06:46 poor fitness levels. However what is perhaps 06:50 most striking about these finding is that 06:53 those individuals who displayed just 06:55 average levels of fitness demonstrated 06:58 marked reductions in overall cancer death 07:01 rates compared with those persons with 07:04 poor fitness levels. Similar to tracking data 07:08 for cardiovascular disease and diabetes 07:12 these results emphasize the importance of 07:14 just getting yourself in the average fitness 07:17 category by accumulating at least 30 minutes 07:21 of moderate intensity physical activity 07:24 on a regular basis. What are some of the 07:29 biological mechanisms that may help explain 07:32 the relationship between physical activity 07:35 and cancer? One possibility is that 07:39 physical activity may provide a lifestyle 07:42 protective effect by enhancing the function 07:45 of the immune system, this idea has been 07:49 tested by injecting laboratory animals 07:52 with certain types of cancer producing 07:54 chemicals assigning them to exercising 07:57 or non-exercising groups and then measuring 08:01 cancer growth. Results from these studies 08:04 have shown that exercise appears to retire 08:08 the growth of cancer at a number of sites, 08:11 in humans moderate physical activity 08:15 like brisk walking has also been shown to 08:20 enhance the function of certain cells 08:22 in the immune system like natural killer cells 08:26 which serve as the body's first line of 08:29 defense against the development 08:31 and spread of cancer. However at more 08:36 intense levels of exercise some short term 08:39 suppression of the immune system 08:41 seems to be present, viewed collectively 08:45 these findings provide further support for 08:48 engaging in a daily routine of moderate 08:51 physical activity, in addition to it's ability 08:55 to strengthen the immune system, 08:58 physical activity may further reduce 09:00 overall cancer risk by improving circulation, 09:03 ventilation, energy balance 09:07 and the ability to repair DNA. 09:12 In general evidence suggests that 09:16 physical activity may significant reduce 09:18 the chance of developing some site specific 09:21 cancers, the strongest data come from 09:25 research indicating that physical activity 09:28 may lower the risk of colon 09:30 and breast cancer by as much as 09:33 30 to 50 percent. Physical activity may 09:37 also exert a protective effect against 09:40 endometrial cancer, prostate cancer 09:43 and lung cancer. While a few researchers have 09:48 attempted to document the influence 09:50 of physical activity on ovarian, pancreatic 09:54 and stomach cancers no clear findings 09:57 have emerged. Let's take a look at the 10:03 association between physical activity 10:06 and certain types of sites specific cancers, 10:10 as mentioned earlier the evidence linking 10:13 physical activity and a reduced risk of 10:16 colon cancer appears quite convincing. 10:20 Out of 45 published studies 38 or 84 percent 10:26 have reported an average decline of 10:30 50 percent in colon cancer risk amongst 10:33 more physically active people in fact 10:37 it's been estimated that if the entire 10:40 adult population in the United States 10:43 increase it's physical activity level by just 10:46 three hours of walking per week which 10:49 translates into a daily walking time of 10:51 about 25 minutes per day there would be 10:55 17 percent fewer cases of colon cancer. 10:59 This trend is supported by result of a study 11:03 involving nearly 48,000 men aged 40 to75, 11:10 in this report the risk of colon cancer was 11:13 decreased by nearly 50 percent in the most 11:16 physically active men when compared 11:19 to their sedentary peers. Specifically 11:23 the greatest protection from colon cancer 11:26 was observed in men who were active 11:28 one to two hours per day conversely men 11:33 who were physically inactive and obese 11:37 displayed a colon cancer risk nearly five times 11:40 higher then that of their active 11:43 and more lean counterparts. 11:46 In a similar study of 89,000 women 11:50 it was found that colon cancer risk dropped by 11:52 nearly 50 percent in women who were 11:56 the most physically active. 11:59 Now what it counts for the relationship between 12:02 physical activity and a lowered risk of 12:05 colon cancer? It's known that exercise 12:10 and physical activity stimulate a process 12:12 called peristalsis or muscle movement 12:16 within the large intestine, 12:18 with enhanced peristalsis the time 12:22 that cancer causing chemical in fecal matter 12:24 remain in contact with cancer, 12:27 with colon cells is decreased thus 12:31 diminishing the exposure of the intestinal wall 12:34 to carcinogens. It is also thought that 12:38 reducing the period of contact between 12:40 carcinogens and colon cells may reduce 12:43 the growth and proliferation of 12:45 these cells. In one study looking 12:49 at the effect of modern exercise on the time 12:51 required for food residue to pass 12:54 completely through the body it was observed 12:57 that running and cycling produced much faster 13:00 transit times compared to a resting condition. 13:05 So in this sense exercise produces 13:09 the same effect on the colon as does 13:11 the ingestion of the dietary fiber, 13:15 it was also been suggested that 13:17 physically activity may lead to a lower 13:19 cancer risk by reducing obesity levels. 13:23 Support for this assertion can be found 13:26 in animal study showing that cancer risk is 13:29 lowered when energy intake is slightly 13:32 reduced below body requirements. 13:36 Both physical inactivity and obesity can raise 13:40 levels of insulin or hormone that increases 13:44 cancer risk by elevating the growth 13:46 rate of cells lining the colon. 13:49 Of course it is also possible that people 13:53 who are physically active eat more 13:55 dietary fiber which would increase 13:58 the protection against colon cancer. 14:02 However in studies where dietary fiber intake 14:05 has been controlled physically activity 14:08 is still shown to independently decrease 14:11 the risk of colon cancer. Is there a link 14:16 between physical activity and 14:18 breast cancer, out of 41 published studies 14:23 25 or 63 percent demonstrated their 14:27 occupational and leisure time physical activity 14:30 was associated with about a 30 percent 14:32 reduction in breast cancer risk. 14:36 In one study of premenopausal females, 14:38 the risk of breast cancer was reduced by 14:41 almost 60 percent in those women 14:44 who exercise in average of more then 14:46 3.7 hours per week or just more than 14:49 30 minutes per day since the start of menses, 14:54 these results highlight the importance of 14:56 leading a modernly active lifestyle 14:58 beginning early in life. In another report 15:03 leisure time physical activity in 15:06 breast cancer risk were documented 15:08 in over 25,000 women, data from this 15:12 investigation reveal that as the level of 15:15 leisure time physical activity increased from 15:18 sedentary to regular exercise, 15:21 the risk of breast cancer decreased by 15:23 37 percent. Moreover the lowest breast cancer 15:29 risk was found among women who were lean 15:32 and regularly exercised. What are 15:36 some of the potential mechanisms underlying 15:38 the relationship between greater levels of 15:40 physical activity and reductions in 15:42 breast cancer risk. Women who have 15:46 exercised rigorously from childhood 15:48 tend to have a later onset of monarchy, 15:51 some missed menstrual cycles and greater 15:55 leanness all of which lower exposure 15:58 of the breast tissue to estrogen. 16:01 Because estrogen promotes the 16:03 proliferation and the vision of the 16:05 breast cells there is a greater chance for 16:08 genetic mutations to take hold that can 16:10 result in the development of cancer. 16:14 Estrogen metabolism also generates 16:16 free radicals which can produce unstable DNA, 16:20 genetic mutations and a greater cancer risk, 16:25 in addition estrogen can stimulate 16:28 the production of receptors for other 16:30 hormones like progesterone that can 16:33 cause breast cancer cells to divide. 16:37 Related to this discussion is the fact 16:40 that obesity and especially abdominal 16:43 obesity can heighten the risk of breast cancer 16:46 by increasing estrogen levels in the body, 16:50 obesity also increases insulin which in turn 16:54 can spur the growth of breast cancer cells. 16:59 Taken together the role that exercise 17:03 may play in altering exposure to sex hormones 17:06 reducing obesity and decreasing levels of 17:09 insulin suggests that the protection against 17:12 breast cancer through physical activity is 17:15 biologically possible. Researchers have also 17:20 investigated the association between 17:22 physical activity and endometrial cancer 17:26 in light of the effects of physical activity 17:28 on the production, metabolism and excretion 17:32 of sex hormones like estrogen 17:34 and progesterone. Although the number of 17:37 published studies on this cancer are 17:40 small a relationship between 17:43 physical activity and endometrial cancer risk 17:46 has been observed. In these reports 17:50 a significantly reduced risk of 17:53 endometrial cancer was observed as 17:56 activity levels increased, 17:59 the protective effect of physical activity on 18:03 prostate cancer, the most frequently 18:06 diagnosed cancer in men is less apparent 18:10 when compared to available evidence 18:12 for cancers of the colon and breast. 18:14 Of 28 published studies 14 or 50 percent 18:20 show that occupational and leisure time 18:23 physical activity significantly decreased 18:26 cancer risk in the prostate by 18:29 10 to 70 percent. In one study involving 18:33 more than 13,000 men those exhibiting 18:36 the highest levels of aerobic fitness 18:38 displayed a 74 percent lower risk of 18:42 prostate cancer compared to men 18:45 who were least fit. The fact that the risk 18:48 for prostate cancer death has been tied to 18:51 higher body mass index values also suggest 18:55 that overweightness and obesity may be 18:58 operative factors in promoting 19:00 prostate cancer. What might explain 19:04 the association between physical activity 19:07 and a lowered risk of prostate cancer in men. 19:11 It has been hypothesized that higher levels of 19:14 testosterone may fuel the growth of 19:17 prostate cancer cells. It is also known 19:21 that athletes have lower levels of circulating 19:23 testosterone compared to non-athletes, 19:26 hence highly active men may end up 19:30 exposing their prostate glands to less 19:33 testosterone there by reducing their risk for 19:36 prostate cancer. Furthermore by 19:41 encouraging a more lean body composition 19:44 physical activity may lower the levels of 19:47 proteins and hormones that could promote 19:49 prostate tumor growth in obese men. 19:54 Lung cancer is the second most common 19:57 cancer among men and women 19:58 in the United States, like prostate cancer 20:02 the potential protective effect of 20:04 physical activity in reducing the risk of 20:07 lung cancer is not as strong as that seen for 20:10 colon and breast cancers. None the less 20:13 it has been speculated that increased 20:16 ventilation and better blood flow to the lungs 20:19 may act to reduce the concentration of 20:22 carcinogenic agents in the breathing passages 20:25 and the length of time that these agents 20:28 are in contact with the lung airways. 20:32 Limited data have shown that for lung cancer 20:34 physical activity can exhort a protective 20:37 effect of between 20 percent 20:39 and 60 percent. In these studies 20:42 it was observed that participation 20:45 in modern intensity physical activity 20:47 reduced cancer risk after adjusting 20:50 for the impact of smoking and other 20:53 potential risk factors. In summary 20:57 physical activity appears to exhort a 20:59 protective effect on certain site 21:02 specific cancers. While more research 21:06 on this topic is certainly warranted 21:08 it appears that the performance of moderate 21:11 intensity physical activity is more 21:14 beneficial then light activities in reducing 21:17 cancer risks. There are some general 21:21 guidelines that are available to help 21:23 prescribe exercise and physical activity for 21:26 otherwise healthy cancer survivors, 21:29 while the goals for cancer survivors 21:31 will vary across individuals reasonable 21:35 expectations might include being 21:37 able to exercise on a regular basis, 21:40 maintaining or improving everyday function, 21:44 optimizing general health, managing 21:47 specific symptoms and side effects of 21:49 medical treatment and preventing diseases 21:52 like osteoporosis, the cancer survivors are 21:56 at a higher risk for it. With respect to 21:59 activity mode walking and cycling are often 22:02 recommended because they are safe activities 22:06 that can be done at a controlled 22:07 moderate intensity and a low impact 22:10 in nature. For certain individuals activity 22:15 may need to be modified based on patient 22:18 preference as well as the short 22:21 and long term treatment effects of surgery, 22:24 chemotherapy, and radiation therapy. 22:28 While the frequency of exercise should be 22:30 at least three to five times per week. 22:33 Exercise done at lighter intensities 22:36 or for shorter time periods may be optimal 22:39 for deconditioned cancer patients. 22:42 While it is recommend that exercise 22:45 duration be at least 20 to 30 minutes 22:48 accumulating shorter physical activity 22:51 bouts with intervening rest periods is a 22:54 reasonable alternative for patients 22:56 who are less fit, or who are experiencing 22:59 severe side effects from treatment. 23:02 With time the volume of exercise performed 23:06 can be raised, first by increasing frequency 23:09 and duration and later by raising 23:13 intensity level. The progression of the 23:16 exercise program should be slowing gradual 23:19 for deconditioned persons and for 23:22 individuals for whom treatment side effects 23:25 might be especially problematic. 23:28 It should also be remembered that 23:30 fluctuations in the ability to perform 23:33 physical activity ought to be expected. 23:36 In addition to the physiological benefits 23:38 that are gained from adopting an active 23:40 lifestyle, the improvement in 23:42 psychological health that results from being 23:44 physically active is a prime significance 23:47 for the cancer survivor. When creating 23:50 a physical activity program for a person 23:53 with cancer it is important to recognize 23:55 that medical treatments and disease related 23:58 declines in physical functions probably 24:01 account for at least some of the 24:03 psychological and emotional burdens 24:05 of the cancer experience, these can 24:08 include depression, anxiety, body image 24:11 concerns, decreased self esteem 24:14 and a loss of control. A successful physical 24:18 activity program is one that is enjoyable 24:20 and builds self-confidence. 24:23 Other factors that may positively impact 24:25 activity programming for the cancer survivor 24:28 include the development of new skills 24:30 and the facilitation of social interaction. 24:35 In an earlier program we discussed barriers to 24:39 exercise and identify it's specific strategies 24:42 to overcome them, for the cancer survivor 24:45 incentives to participate in exercise 24:48 and barriers preventing exercise also exist, 24:53 not surprisingly many of the incentives 24:55 for the cancer survivor such as maintaining 24:58 a normal lifestyle, feeling better, 25:01 improving psychological well being 25:03 and securing general health benefits are 25:07 similar to those which might be appropriate 25:09 for the general population. 25:10 However other incentives like recovering 25:14 from surgery and treatment, 25:15 gaining control over cancer and once life 25:19 and coping with the stress of cancer 25:21 are unique to the cancer survivor, 25:24 likewise barriers to exercise such as 25:27 bad weather, fatigue and lack of time 25:30 are common to many individuals, 25:32 others like nausea and diarrhea 25:36 would again be specific to the patient 25:39 with cancer. It is critical that the 25:42 medical support team recognize the cancer 25:44 survivors will have special incentives 25:47 and barriers to physical activity that must be 25:50 addressed when creating a personalized 25:53 physical activity program. I like to end 25:57 today by recounting a personal story 25:59 of a woman from Australia who is a 26:02 long term survival of breast cancer. 26:05 It has been more than three decades 26:07 since Bettina Woodburn was diagnosed with 26:10 breast cancer, after learning about 26:12 the warning signs of breast cancer 26:14 Bettina checked her breasts and found a lump 26:18 soon there after she underwent both 26:21 lumpectomy and a mastectomy. 26:24 Following these surgeries Bettina 26:26 returned to being a wife and a mother of 26:28 four children but she was in her own words 26:32 shattered and in shock from the entire 26:35 experience. Eventually Bettina became 26:39 more positive about her cancer recovery 26:41 and spent the time between the ages of 26:44 50 and 60 becoming very physically fit in order 26:48 to fight the further spread of the diseases. 26:50 She also became mentally fit earning 26:54 three academic degrees, in addition to 26:57 kayaking and bicycling to strengthen 26:59 and improve the efficiency of her arms 27:01 and legs she joined what is known as 27:04 Veteran Athletics when she was 60 27:06 and competed in running, throwing 27:08 and jumping events. At one point Bettina 27:12 held 15 Australian records in the Veteran 27:15 and Masters Games and she was the medalist 27:18 in the world games in Rome and Melbourne. 27:20 She has also kayaked to raise money for 27:23 breast cancer research and now over 80 27:26 she still rides a road racing bike. 27:29 Bettina's story is inspiring not only 27:33 because she successfully overcame 27:35 breast cancer but also because 27:37 she fought the demons of self doubt 27:39 and negativity and adopted a 27:42 positive attitude about her recovery. 27:45 For Bettina, physical activity was an 27:47 important part of her recovery plan 27:49 and it is something that has become 27:51 part of her normal lifestyle. 27:52 When asked about the most important 27:55 health message she could give to other women 27:57 who have cancer her response was this, 28:00 stop grieving and realize that you can 28:02 fight cancer. Watch your health 28:05 and aim for fitness and fun, 28:06 this is a message that can apply to all of us. 28:09 So until next time keep moving 28:12 step by step towards better fitness. |
Revised 2014-12-17