Great runner, cancer foundation, exercise-oncology researcher, and cancer institute. Please support!
Source: GRETE’S PLACE
Great runner, cancer foundation, exercise-oncology researcher, and cancer institute. Please support!
Source: GRETE’S PLACE
Exercise is good for the immune system but what about high volume, high intensity, chronic (long-term) exercise? For cancer patients, a couple of things may be worth considering, but first a few things about immune cells. In a general sense, cancer is a failure of the immune system to detect and eliminate defective cells, or maybe more accurately, the ability of cancer cells to evade detection from immune cells.
Two categories of immune cells are: innate immune cells; and, adaptive immune cells. Natural Killer cells (NK cells) are a part of the innate immune system and they respond quickly to tumor formation and virally infected cells. T-cells are a part of the adaptive immune system. T-cells remember previous invaders, and cancer, and respond faster the second time to the same invader. Moderate intensity exercise and life long aerobic fitness improves aspects of both of these immune cell types. However, high volume, high intensity, long-term extreme exercise can have negative effects (1,2).
A study (3) followed Ironman competitors training for 6 months prior to the event and for a few weeks afterwards. The researchers found that by the end of study period the ratio of some T-cell subtypes changed to a composition that an older person is more likely to have. Naive T-cells, which are highly responsive mature T-cells, decreased, while terminally differentiated T-cells (senescence) increased. Terminally differentiated T-cells are not as ‘nimble’ as naive T-cells in responding to invaders, and the ratio between the two can change as one ages – more terminally differentiated T-cells accumulate and less naive T-cells are found. This change is thought to make the elderly more susceptible to infections. However, increasing aerobic fitness can lower the proportion of age-related senescent T-cells and increase naive T-cells, regardless of age (4), but maybe only to a point, as elite endurance athletes are known to get more upper respiratory infections and changes in immune cells are thought to play a role in this (5).
Another piece in this exercise puzzle is a virus, Cytomegalovirus (CMV). CMV is a common herpes virus infecting approximately 50% of American adults, and that percentage increases with age. CMV affects the exercise response of NK cells, increasing their numbers and cytotoxicity (killing ability). However, that changes at exercise intensities eliciting a blood lactate concentration of 4 millimoles, which is about +15% of the blood lactate threshold (as defined by Weltman, A., 1995). This is an intensity that many endurance athletes periodically train at in order to improve performance – tempo runs for marathon runners are an example. After exercise that induces 4 millimoles blood lactate, NK cell numbers and cytotoxicity are decreased, but not in healthy individuals, only in CMV infected individuals, and regardless of sex (6).
So what does this mean for cancer patients wanting to do a triathlon, marathon, or ultra? Right now there isn’t enough evidence to change the general American College of Sports Medicine (ACSM) guidelines of 150 minutes per week of moderate intensity exercise or 75 minutes per week of vigorous exercise. Although a recent breast cancer study (7) found that 300 minutes per week of moderate intensity exercise was best for post-menopausal breast cancer patients who were not on hormones. Surprisingly, another study found that higher levels of cardiorespiratory fitness was associated with higher risk of prostate cancer (8), the CMV status of those subjects was not reported and may not be known. Outside Magazine recently did an article (9) on the deleterious effects ultra-marathons has had on some participants. Perhaps CMV status or changes in T-cell proportions may be emerging as important markers to follow. Exercise can help protect us against infection and fight tumors but that does not also mean greater amounts of exercise is better. Until more evidence is presented, the ACSM exercise recommendations, as generic as they are, appear to be about right for cancer patients, and maybe particularly for those who are CMV positive.
For more in-depth information about exercise and immunity, a couple of recent articles are worth reading (10,11,12), if you can get full access (12).
The impact of 6-month training preparation for an Ironman triathlon on the proportions of naïve, memory and senescent T cells in resting blood. Coagrove, C., et al. Eur J Appl Physiol (2012) 112:2989–2998.
Aerobic fitness is associated with lower proportions of senescent blood T-cells in man. Spielmann, G., et al. Brain, Behavior, and Immunity 25 (2011) 1521–1529.
Acute exercise preferentially redeploys NK-cells with a highly-differentiated phenotype and augments cytotoxicity against lymphoma and multiple myeloma target cells. Part II: Impact of latent cytomegalovirus infection and catecholamine sensitivity. Bigley, A.B., et al. (Article in Press) Brain, Behavior, and Immunity xxx (2015) xxx–xxx.
Effects of a High vs Moderate Volume of Aerobic Exercise on Adiposity Outcomes in PostmenopausalWomen. A Randomized Clinical Trial. Friedenreich C.M., et al., JAMA Oncol. doi:10.1001/jamaoncol.2015.2239.
Midlife Cardiorespiratory Fitness, Incident Cancer, and Survival After Cancer in Men. The Cooper Center Longitudinal Study. Lakoski, S.G., et al., JAMA Oncol. 2015;1(2):231-237. doi:10.1001/jamaoncol.2015.0226.
A recent study (1) found that a high level of cardiorespiratory fitness (CRF) was associated with an increased risk for localized prostate cancer. The reasons for this are unknown. The researchers speculate that perhaps this group was more likely to undergo preventative screening or detection. However, higher CRF still showed a 32% decreased risk of cancer specific death for lung, colorectal, or prostate cancers; or 68% decreased risk of death from cardiovascular disease (CVD). Note: some cancer treatments can be toxic to the heart.
From: Midlife Cardiorespiratory Fitness, Incident Cancer, and Survival After Cancer in Men: The Cooper Center Longitudinal Study.
Figure Legend: Cardiorespiratory Fitness (CRF) and Risk of Incident Lung, Colorectal, and Prostate Cancer. The low CRF group is the referent group relative to moderate and high fitness. The error bars for moderate and high fitness represent the 95% confidence limits. Adjusted for age, examination year, body mass index, smoking, total cholesterol level, systolic blood pressure, diabetes mellitus, and fasting glucose level.
The authors distinguish CRF from physical activity (I believe research data for both could be provided by valid and reliable activity trackers):
“Cardiorespiratory fitness is also highly reproducible and objectively assessed via incremental exercise tolerance testing compared with physical activity, which is largely determined by self-report questionnaires [and/or activity trackers?]. A prior study demonstrated that CRF is be a more potent marker of mortality than physical activity. As such, given the current study findings and prior evidence, we contend that measurement of CRF should be used more frequently in the cancer prevention setting.”
I agree. Furthermore, I would like to see physical activity, CRF, or aerobic capacity assessed when the cancer diagnosis process begins. How beneficial would it be to tie fitness to an actual biopsy tissue specimen? It’s interesting that CRF in the Cooper Clinic Longitudinal Study was assessed by the duration of performance achieved on a maximal treadmill test (2). Then, based on subjects’ performance time, maximal oxygen uptake (VO2max) and maximal METs achieved were estimated, not measured. If estimates can be used to assess CRF then it’s possible that some activity trackers could also be used. Granted, screening patients before a CRF test is recommended, but some activity tracking data may already provide an adequate assessment of CRF. A few devices already assess VO2max using heart rate, and with acceptable errors (for field measurements) in the 6-7% range (11, 12). Stratifying data from activity trackers may be an important part of sorting its value: data for showing a training effect requires good accuracy; less accurate data is probably acceptable to assess CRF; and, data for tracking physical activity volume (MET-hours per week, etc.) can perhaps be the least precise of these – particularly since current population research using questionnaires tends to overestimate actual physical activity (13).
In discussing limitations of their study the authors mention something I believe may be significant for exercise-oncology research, and which I think validated activity trackers may be able to provide data for:
“CRF was assessed years prior to a diagnosis of lung, colorectal, or prostate cancer or death in men diagnosed as having cancer. Thus, it is not known how changes in CRF and related behaviors, such as physical activity from the initial preventive health care to cancer diagnosis as well as changes in CRF and physical activity after diagnosis, may have had an impact on these current findings.”
I believe that exercise during the time from cancer diagnosis until first treatment will be found to have a positive impact on cancer treatments, treatment side effects, and on survival. Sophisticated activity trackers that also estimate VO2max, or measure heart rate variability (HRV), which is related to CVD, have the potential to provide data in and around the diagnosis/treatment time period. Furthermore, they can provide data across more cancer types by doing it in a more cost-effective manner than mailing out questionnaires or doing a CRF test on every cancer patient. One overlooked benefit of activity trackers is that consumers subsidize the data.
Some useable physical activity data already exists in activity tracking databases but sits there underutilized. Most physical activity data needs standard medical codes to improve its interoperability. Other data could be retooled by correcting METs, which could provide more accurate estimates of energy expenditure (4, 5, 6, 7, 8), population specific intensity levels (9, 10), and might influence adherence to exercise training programs. Regarding METs, an issue for some researchers is that the ‘standard’ MET (3.5 ml oxygen/kg/min) was based on the measurements derived from one 70 kilogram, 40-year-old man (5), and then applied to survey research. Conversely, some activity trackers use ‘standard’ MET values from the Compendium of Physical Activities, which are intended for survey research, to estimate the energy expenditure and exercise intensity for an individual, which the Compendium advises is not its intended purpose.
Besides valid data, another issue activity trackers face is how should data be displayed or reported within an Electronic Health Record (EHR)? Doctors are already over-worked and many complain about the burden of EHRs, adding physical activity data to their workload and expecting them to do something proactive with it (without reimbursement too) is not going to happen. Make physical activity data easy for doctors to accommodate: summarize activity tracker data into an indicator of ‘compliance‘ or ‘non-compliance‘ with recommended physical activity guidelines, and provide that to an EHR. For research, and for the more inquisitive and less time constrained physician, the underlying data supporting a compliance indicator could be accessible via EHR patient portals (e.g. EPIC’s MyChart).
Finally, a new study (3) found the ActiGraph GT3X+ accelerometer not to be very accurate at low and moderate intensity levels. Of the few validation studies done on accelerometer based activity trackers, some were validated against the Actigraph as the criterion measure. However, this study itself also missed an opportunity for better measurement when they estimated Resting Metabolic Rate (RMR) using the Schofield equations rather than measuring it with the Oxycon Mobile system they had – RMR is essentially what 1 MET is. The study’s authors do disclose that they have receive funding support from Bodymedia, which Jawbone recently bought.
There is more to be sorted out in the consumer fitness/activity tracking eco-space. I think devices and apps that produce valid and reliable data can make an impact in exercise-oncology research, particularly in the time periods surrounding diagnosis and treatment.
1. Lakoski, S.G., et al. Midlife Cardiorespiratory Fitness, Incident Cancer, and Survival After Cancer in Men The Cooper Center Longitudinal Study. JAMA Oncol. 2015;1(2):231-237. doi:10.1001/jamaoncol.2015.0226
2. Pollock ML, Bohannon RL, Cooper KH, et al. A comparative analysis of four protocols for maximal treadmill stress testing. Am Heart J. 1976; 92(1):39-46.
3. Kim, Y., Welk G.J. Criterion Validity of Competing Accelerometry-based Activity Monitoring Devices. Med. Sci. Sports Exerc. 2015 Apr 23. [Epub ahead of print]
4. McMurray, R.G., et al. Examining Variations of Resting Metabolic Rate of Adults: A Public Health Perspective. Med. Sci. Sports Exerc., Vol. 46, No. 7, pp. 1352–1358, 2014.
5. Byrne, N., et al. Metabolic equivalent: one size does not fit all. J Appl Physiol 99: 1112–1119, 2005.
6. Kozey, S., et al. Errors in MET Estimates of Physical Activities Using 3.5 ml·kg–1·min–1 as the Baseline Oxygen Consumption. Journal of Physical Activity and Health, 2010, 7, 508-516.
7. Wilms, B., et al. Correction factors for the calculation of metabolic equivalents (MET) in overweight to extremely obese subjects. International Journal of Obesity (2014) 38, 1383–1387.
8. Hall, K., et al. Activity-Related Energy Expenditure in Older Adults: A Call for More Research. Med Sci Sports Exerc 2014 Dec;46(12):2335-40.
9. Blair, C.K., et al. Light-Intensity Activity Attenuates Functional Decline in Older Cancer Survivors. Med Sci Sports Exerc 2014 Jul;46(7):1375-83.
10. Herzig, K-H, et al. Light physical activity determined by a motion sensor decreases insulin resistance, improves lipid homeostasis and reduces visceral fat in high-risk subjects: PreDiabEx study RCT..International Journal of Obesity (2014), 1–8
11. Montgomery, P.G., et al. VALIDATION OF HEART RATE MONITOR–BASED PREDICTIONS OF OXYGEN UPTAKE AND ENERGY EXPENDITURE. Journal of Strength and Conditioning Research 23(5)/1489–1495.
12. Lebouf, SF., et al. Earbud-based sensor for the assessment of energy expenditure, HR, and VO2max. Med Sci Sports Exerc 2014;46(5):1046-52.
13. A systematic review of reliability and objective criterion-related validity of physical activity questionnaires. International Journal of Behavioral Nutrition and Physical Activity 2012, 9:103 pgs 1-55.
Yep, there are issues with activity trackers. Just because a tracker may have a well-known name doesn’t mean it is accurate, or accurate for all activity measures. And just because a tracker says it measures variable “X” doesn’t mean it is measured accurately. Very few activity trackers and fitness apps have been validated, and if they have, results may not match the assertions marketed by the product developers.
Most activity tracker data is not yet ready for entry into Electronic Health Records (EHRs). First, products need to be validated, then their measures need to have standard codes (LOINC, SNOMED, UCUM) attached to them before the data should be accepted into EHRs or research databases. For some unknown reason, exercise stakeholders lag far behind other key adopters of health IT codes (‘big” labs, all health-related federal agencies, care organizations, insurance companies, EHR vendors, and Health Information Exchanges; source: LOINC) in utilizing the codes for the variables they measure.
Regarding validation studies, I applaud FirstBeat for their extensive listing of studies on, or using, their products/technology (I receive no compensation nor am I an investor or currently an owner of a FirstBeat product). It’s often difficult just to find out how a fitness app or activity tracker measures (estimates) calories – which equation is used, and equations are misused e.g. Resting Metabolic Rate (RMR) for Basal Metabolic Rate (BMR). Simple errors like this can contribute 10-20% overestimation of calories and energy expenditure (1).
Furthermore, RMR can vary significantly with gender, age, or obesity (2,3,4,5). However, most physical activity observational studies, which is what activity trackers are suited for, still use the ‘standard’ MET (Metabolic Equivalent) oxygen value of 3.5 ml/kg/min as RMR. This RMR few adults have, most are significantly lower (2,3,4,5). Since the ‘standard’ MET is widely used in observational studies, and most of those studies use questionnaires that have their own validity issues (6), accuracy can vary significantly from an MET that was actually measured in a lab.
Activity trackers have the potential to gather more accurate physical activity measures compared to the same measures gathered from patient reported questionnaires. This can be a good thing for observational research. However, if activity trackers also defer to the ‘standard’ MET, use metabolic equations incorrectly, are not validated, do not attach their measures to standard health IT codes, and importantly, if EHRs, researchers, and users do not demand that they do, then tapping into their research potential will be delayed.
1. Dietary Reference Intakes: Energy, Carbohydrate, Fiber, Fat, Fatty Acids, Cholesterol, Protein, Amino Acids. IOM 2005; page 112.
2. Metabolic equivalent: one size does not fit all. J Appl Physiol 99: 1112–1119, 2005.
3. Examining Variations of Resting Metabolic Rate of Adults: A Public Health Perspective. Med. Sci. Sports Exerc., Vol. 46, No. 7, pp. 1352–1358, 2014.
4. Errors in MET Estimates of Physical Activities Using 3.5 ml·kg–1·min–1 as the Baseline Oxygen Consumption. Journal of Physical Activity and Health, 2010, 7, 508-516.
5. Correction factors for the calculation of metabolic equivalents (MET) in overweight to extremely obese subjects. International Journal of Obesity (2014) 38, 1383–1387.
6. A systematic review of reliability and objective criterion-related validity of physical activity questionnaires. International Journal of Behavioral Nutrition and Physical Activity 2012, 9:103 pgs 1-55.
This video is how I see exercise data in oncology. Of all the training I’ve done, which I recorded but which no one else did, and of all my data sitting in Garmin, Moves, RunKeeper, Moov, and MiFitLife databases, not one byte of it is in my EHR (Electronic Health Record). However, during my stay in a hospital isolation ward for my allogeneic stem cell transplantation (donor HSCT) my bowel movements were recorded and entered into my EHR. Exercise affects gut microbiota (bacteria) and immune function (1), and diversity of gut microbiota correlates to improved survival from a donor HSCT (2). Did the exercise I did prior to and throughout my stem cell transplantation preserve my gut microbes, affecting my immune system, which helped me breeze through stem cell transplantation? Who knows? But since the data for all this exists, it sure would be nice if it were gathered together in the same place (EHR) in order for me and other patients to find out.
At home, my treadmill is Bluetooth compatible, but none of the workout miles I’ve done on it are in my EHR either.
Outside, sigh … you get the picture. Fitbit, Nike, Jawbone, Garmin, or ‘fitness this’ and ‘fitness that’ app/device, please do not spend one more dime on another advertisement touting your latest model or bells and whistles. Instead, hire more (or better) IT people proficient in medical coding/HIT, exercise science, and data interoperability, and free our data from your proprietary databases so that it can be used, if we agree, within EHRs for research. Looking at a graph of the last few months of my training does not benefit others, no matter how inspiring some may think my training to be. We are losing too many people like Laurie Becklund, and activity tracker data on us may be significant toward improving survival from cancer. Exercise decreases cancer metastasis, in mice studies anyway (3, 4, 5). Is the data right at our wrists for metastatic significance in humans?
ResearchKit, can data flow back into subjects’ EHRs? Exercise researchers, how much of the study data generated from subjects goes back to them so that it can enter their EHR? EHR vendors, do your patient portals even accommodate exercise data should it become useable? National Coalition for Cancer Survivorship, can we improve the Journey Forward, Survivorship Care Plan tool’s small section on exercise and populate it with valid activity tracker data similarly to how it is populated with cancer registry data?
This is not rocket science, neither is it a billion dollars in new drug development that marginally improves survival for a few months, this is already here, we just have to capture it in ways that can actually be used to save lives.
There’s a lot of interest in tracking physical activity, ranging from simple weight loss tools to more high-tech gadgets for mountain climbing or ultra-endurance events. Altitude, distance, speed, calories, heart rate, steps, type of activity, intensity, and even time spent sitting, are just some of the variables being recorded. Smartphone ‘apps’, watches/bands, heart rate straps, pocket/clip-on devices, ear buds, and web-based diaries are able to collect these variables. However, few of these devices, including ‘apps’, have been validated – scientifically tested for accuracy against a criterion (standard). This is important if we want to use consumer fitness data (Patient-Generated Health Data – PGHD) for more than just personal curiosity, which typically wanes after a few months. If you haven’t validated your device, do it. If you fear the results, then improve your product so that it accurately records valid fitness measures.
For exercise-oncology research, and exercise research in general, in many ways PGHD from validated activity trackers can be more accurate than Patient Reported Outcomes from validated questionnaires. Either way, data comes from patients, but some fitness trackers are as accurate as the criterion (6). This I like because it will require other fitness trackers to improve accuracy. Developers unwilling to validate and improve their device will be relegated to the Big Data sidelines, if they survive at all. Regardless of how sophisticated and proprietary a devices sensors are, most end measures will be the same as from other devices – energy expenditure – kcal, estimated VO2, METs. No longer should an app be able to use a metabolic equation inaccurately and have their data be relevant.
Validated activity trackers have the potential to expand physical activity related observational research to every Electronic Health Record (EHR) – this is a big number, over a billion, which is much larger than the fitness geek marketplace. For small population cancer types, which get little, or no, exercise research due to their inability to recruit enough patients from single or multiple healthcare facilities, this could do wonders for statistical power. Might we find similar benefits for exercise among other cancer types as have been found in brain, breast, colorectal, and prostate cancers? Will we discover more information about intensity, duration, frequency, and type of exercise regarding proximity to diagnosis and treatment?
For cancer patients, having our physical activity automatically tracked, medically coded, encrypted, summarized, and made available for upload into our EHRs, this may be the least invasive thing involving our body, and with the lowest cost per survival outcome.
1. The microbiota: an exercise immunology perspective. Bermon, S., et al. Exercise Immunology Review 2015;21:70-9.
2. The effects of intestinal tract bacterial diversity on mortality following allogeneic hematopoietic stem cell transplantation. Taur, Y., el al. Blood, 14 August 2014 x Volume 124, Number 7.
3. Effects and potential mechanisms of exercise training on cancer progression: A translational perspective. Allison S. Betoff, Mark W. Dewhirst, Lee W. Jones. Brain, Behavior, and Immunity 2013 Mar;30 Suppl:S75-87.
4. Exercise modulation of the hosttumor interaction in an orthotopic model of murine prostate cancer. Jones, LW., et al. J Appl Physiol (1985). Jul 15, 2012; 113(2): 263–272.
5. Exercise modulation of the host-tumor interaction in an orthotopic model of murine prostate cancer. Jones, LW., et al. J Appl Physiol 113: 263–272, 2012.
6. Earbud-based sensor for the assessment of energy expenditure, HR, and VO2max. Lebouf, SF., et al. Med Sci Sports Exerc 2014;46(5):1046-52.
Don’t sweat the little things!
I don’t like waiting … waiting for results, waiting in lines, waiting in traffic, or waiting for elevators. Regarding the latter, if I’m only going 1-3 flights, stairs are often quicker anyway, plus, I feel like I’m doing something pro’active’ for my health. A typical flight of stairs might be 16-20 steps, that’s 8-10 repetitions lifting my entire body weight with each leg. Do this a few times a day, all year-long, as a habit, and it can help maintain leg strength and muscle mass. Consistently taking the elevator can contribute to loss of leg strength and muscle mass. Use it or lose it – just like muscles that atrophy from lack of use while in a cast.
A hidden downside to losing muscle mass is that it can contribute to weight gain, fat weight. Muscles are good calorie burners, when used, if not used, they atrophy. If one continues eating what they normally do, they will gradually put on weight, because less of the calories consumed will being burned by muscle, so the unused calories get stored as fat. Initially, this small amount of weight may hardly be noticeable, but after a number of years it can be substantial, affecting health and quality of life. This makes climbing stairs more tiring, which can perpetuate elevator use and de-conditioning.
Major lifestyle changes, including exercising or the lack thereof, can start this way. Don’t overlook the little things in a day – like taking the stairs or shopping – embracing these small physical tasks can lead to change. Shopping provides another simple opportunity to make a small change. Park farther away from the doors rather than waiting for a spot up close, or, return your cart. This may seem trivial, and in terms of calories burned, it may be, but it helps change the habits of our mind, habits which often prevent us from getting out the door for walks or other forms of exercise.
During chemotherapy, stairs served as my unofficial barometer of drug efficacy. Prior to my cancer diagnosis I found myself getting tired after going up a single flight of stairs, my quads would burn as if I had just run up a hill. This was a big warning sign that something was wrong with me. Each day after starting chemo I would walk up stairs to see how my legs reacted, after a few days I notice a significant difference – my quads did not burn after getting to the top. I knew then that the drugs were working, they were killing the cancer and I started to regain the weight I had lost from cancer related muscle wasting (cachexia). For cancer patients with balance issues and wanting to use stairs, having someone assist you would be a good idea, certainly, use the handrail.
For those cancer patients accustom to exercising, yet finding themselves preparing for cancer treatment, in the midst treatment, or recovering from it, they might have to lower their exercise expectations. I’ve talked with a number of cancer survivors frustrated about feeling lousy during workouts, or unable to complete a workout like they could before cancer. First, I commend them for continuing to exercise throughout their cancer experience. However, cancer treatments can have a significant effect of on the body – anemia, muscle weakness from anti-inflammatory steroids, lymphedema, surgical pain and tightness, neuropathy in the hands and feet, and the yet unknown sources of treatment related fatigue. In spite of these treatment related obstacles, many cancer patients do exercise, and some quite a lot. However, returning to normal gradually, or with different strategies, may be in order rather than jumping right back into their old workout routine.
One strategy I and others have found helpful, and has long been touted by former US Olympic marathoner, Jeff Galloway, is walk/run. For me, building up to walking 4.2 miles per hour at 11% grade on my treadmill, a good workout in itself, became physically awkward, running seemed like it would be more comfortable. However, starting out running a little bit at a time was easier than trying to cover 3 miles all at once right out of the gate. I used walk/run, beginning with walking 100 meters, then running 100 meters. That soon progressed to 200 meters, 400 meters, then eventually 3 miles straight, and soon I was back to my normal running routine. Rest/exercise, coast/pedal-paddle-row, float/swim, etc., could be applied to other activities.
A number of cancer survivors have returned to the highest levels of competition as professional athletes: tennis players Ross Hutchins and Alisa Kleybanova; hockey players Mario Lemieux and Saku Koivu; major league pitchers Jon Lester and Dave Dravecky; and runner Gabe Grunewald; among many others. The fitness demands of those sports are significant, yet their bodies recovered, and so can yours, probably not to the level of those professionals, but to a level where you are not confined to the couch. Little things can add up!
I often read stories about cancer patient’s (survivor, warrior, thriver, whatever we want to be called) physical accomplishments before, during, or after treatments – marathons, triathlons, ultras, century rides – all impressive stuff, even outside the realm of cancer. The accomplishments seem understandable too, since exercise has been found to:
Interestingly, more exercise did not reduce risk any further in the breast (1) or brain cancer studies. However, for their results, the brain cancer subjects had to exceed the recommended physical activity levels (6) of 150 minutes of moderate intensity exercise per week. Walking was also as good as running in the brain cancer study, subjects just had to walk farther.
What does this all mean for those of us affected by cancer? Well, for the cancers mentioned above, if you’re not moving at the levels showing significance, perhaps it is time to get clearance from your physician, and start. Practically, make exercise or physical activity a part of your weekly schedule. It is easy to fill up your calendar with other things and people but forget to plan you into your week. Take a good look at your week, find days and times that work best to accomplish what you want, then write you into those time slots, and keep the appointment. Book others to meet with you if needed, guilt can be the right motivator sometimes.
Hypothetically, what if completing an Ironman Triathlon improved survival by 80%, would cancer patients, the majority of whom are sedentary, start training? I wouldn’t be surprised if many did, determination can be great when faced with a cancer diagnosis. However, even if willing to simply change their lifestyle, or intensely train for an Ironman, are we already hindering patients’ ability to do so by not pre-habilitating (8) them for the insult some treatments inflict on the body? If most cancer patients do not already like to exercise, how are we ever going to convince them to start if we let their physical function decline further prior to or during the treatment process?
For those of us already in the exercise choir, and for cancer types other than those listed above, how much exercise is enough, and what may warrant caution (9) or be too much? Unfortunately, most fitness stories remain just that, stories, unless we happen to be in a study, because, until physical activity is routinely recorded in oncology we will never know to what extent many physical accomplishments affect cancer survivorship (the ‘survivorship beginning at diagnosis’ definition). Most of us in the cancer exercise choir, myself included, are just figuring it out as we go along, sometimes overdoing it (7), or maybe we’re not doing enough, and we share what we’ve learned with others. Ironically, in spite of all the data we generate when training with our consumer fitness tools, there still isn’t the right statistical data to guide many of us.
Missing data …
A physical activity profile (using a short, scientifically validated, questionnaire) is not routinely recorded when extracting biopsy tissue from patients. Is there evidence in tissue samples that could correlate physical activity to cancer treatment response rates and survival? How are tissue samples different, if at all, between those who exercise versus those who don’t? If different, can the differences be exploited to improve cancer treatment outcomes or to develop new drugs? Exercise and physical activity are positively affecting survival for those cancers listed above, but how is this happening? What are the physiological mechanisms, and are we overlooking routine biopsies as sources of evidence? Exercise physiologists sometimes pay study volunteers and take muscle biopsy samples to find out what exercise did. In oncology, other than pathology, how much thought is given to our biopsy samples, which patients pay for, and exorbitantly too?
I wouldn’t limit recording patients’ physical activity to biopsies only, we should be updating fitness profiles at diagnosis, first treatment, scans, and subsequent healthcare visits too. The studies mentioned above were observational ones done over a number of years, some only assessing physical activity every two years (1,3), which doesn’t allow for teasing out information in the weeks specifically surrounding a cancer diagnosis or treatment. Some physical activity questionnaires have gone electronic, but collecting data using paper forms, interviews, and calls to subjects is still done. In today’s electronic world this sounds archaic, but this is how the best observational evidence has been obtained so far.
Or … data to nowhere
With all the new consumer fitness products available we are still unable to get much of the data they generate into our electronic health records (EHRs). My Garmin data, Moves data, and the information I type into my training and treatment log, all just sit there in electronic form somewhere in cyberspace. My information cannot be pooled with the fitness data from others to search for statistical significance. You can be sure the consumer fitness developers know a lot of things about me, but the products they have developed are generating data that goes nowhere – lots of data rather than ‘Big Data’ – my cancer and fitness story has no statistical power even though plenty of Information Technology (IT) is attached to it.
Recent announcements regarding consumer fitness and IT may change this and move us closer to continuously updated physical activity profiles by using data automatically uploaded through privacy ensured patient portals (EPIC’s ‘MyChart’ would be a good example). Physical activity information could then be accessible when needed by clinicians from EHRs, and more importantly, tied to pathology, treatment, and other information within EHRs. Apple’s collaboration with The Mayo Clinic, Nike, and the prominent EHR system, EPIC, appears to be headed in this direction. However, without the broad use of internationally standardized exercise and physical activity codes for the common measures most exercise stakeholders are recording – steps, calories, heart rate, etc. – integrating the fitness data into EHRs will remain problematic. Medicine wants valid standardized data and evidence before they will change clinical practice. Our fitness stories, with isolated data on only one person, will not change clinical practice.
There is interest among cancer patients in allowing their data to be shared for research purposes, 87% reporting a willingness to do so (10) as long as privacy was adequately addressed. How many of them have stories on the extreme ends of the physical activity spectrum and how is cancer survivorship going for them out there? Fitness stories may motivate or guide others, but we also need statistical significance in order to impact clinical practice.
1. Holmes MD, et al., Physical activity and survival after breast cancer diagnosis. JAMA. 2005;393:2479-86.
2. Meyerhardt JA, et al., Impact of physical activity on cancer recurrence and survival in patients with stage III colon cancer: findings from CALGB 89803. J. Clin Oncol. 2006: 24:3535-41.
3. Giovannucci EL, et al., A prospective study of physical activity and incident and fatal prostate cancer. Arch. Intern. Med. 2005:165:1005-10.
4. Williams PT, Reduced risk of brain cancer mortality from walking and running. Med. Sci. Sports Exerc. 2014 May;46(5):927-32.
5. Irwin ML, et al., Influence of pre and postdiagnosis physical activity on mortality in breast cancer survivors: the health, eating, activity, and lifestyle study. J. Clin. Oncol. 2008:26:3958-64.
6. Schmitz K.H, et al., American College of Sports Medicine Roundtable on Exercise Guidelines for Cancer Survivors. Med Sci Sports Exerc. 2010 Jul;42(7):1409-26.
7. Kano S, et al., [A case with myositis as a manifestation of chronic graft-vs-host-disease (GVHD) with severe muscle swelling developed after aggressive muscular exercise.] Rinsho Shinkeigaku. 2003 Mar;43(3):93-7.
8. Julie K. Silver, MD and Jennifer Baima, M.D. Cancer Prehabilitation: An opportunity to Decrease Treatment-Related Morbidity, Increase Cancer Treatment Options, and Improve Physical and Psychological Health Outcomes. Am J Phys Med Rehabil. 2013 Aug;92(8):715-27.
9. Stan, D, et al., Pilates for Breast Cancer Survivors: Impact of Physical Parameters and Quality of Life After Mastectomy. Clinical Journal of Oncology Nursing. Volume 16, Number 2; pp:131-141.
10. Rechis, R, et al., The Promise of Electronic Health Information Exchange: A LIVESTONG Report.
The Future of Medicine Is in your Smartphone. Eric J. Topol, MD. The Wall Street Journal, 1/9/2015.