Physical activity for cancer patients

Cancer is an important cause of both morbidity and mortality, currently accounting for approximately 1 of every 4 deaths in North America.1,2 However, survival rates are continually increasing, as diagnostic and surgical techniques are improved and ever more effective local, regional, and systemic therapies are introduced. Approximately 66% of patients now live for at least 5 years following a first diagnosis of cancer, and more than 14.5 million North Americans live with such a history.1,2 Today’s family physician must thus be prepared not only to diagnose cancer, but also to provide appropriate lifestyle advice to manage the long-term consequences of cancer diagnosis and therapy. There are diverse physiologic, psychological, and psychosocial responses to both the diagnosis and the treatment of cancer.3–8 The range of effects calls for a multidisciplinary approach, with physical activity (PA) and exercise training interventions increasingly becoming integral to long-term patient management. Conventional cancer therapies induce adverse symptoms, often with unfavourable lifestyle changes, including a decrease in habitual PA and weight gain.9 These changes have negative effects on patients’ quality of life and can limit their ability to undertake the activities of daily living. However, increasing evidence indicates that both of these adverse developments can be attenuated by participation in regular PA.5,6 On the basis of this burgeoning evidence base, several investigators and clinics have started to examine the important contribution of PA and exercise training to supportive care before, during, and following cancer therapy. In general, gains in cardiorespiratory fitness have been accompanied by decreased fatigue and enhanced overall quality of life.3–8 Cancer-specific, evidence-based assessments of the risks and benefits of PA are thus needed by family physicians, qualified exercise professionals, and other members of the allied health team. This article provides an executive summary of findings from a systematic review of the cancer-specific literature,10 undertaken as one in a comprehensive series of analyses examining the risks of PA in patients with various chronic diseases. The information contained in this article forms the foundation for the newly created Physical Activity Readiness Questionnaire (PARQ+) and electronic Physical Activity Readiness Medical Examination (ePARmed-X+).11 We briefly discuss PA risk assessment in patients with cancer based on currently available adverse event–related data, and introduce decision trees that facilitate clinical decision making for the family physician

Systematic review of standing and treadmill desks in the workplace

Introduction Standing and treadmill desks are intended to reduce the amount of time spent sitting in today's otherwise sedentary office. Proponents of these desks suggest that health benefits may be acquired as standing desk use discourages long periods of sitting, which has been identified as an independent health risk factor. Objectives To analyze the evidence for standing and treadmill desk use in relation to physiological (chronic disease prevention and management) and psychological (worker productivity, well-being) outcomes. Methods A computer-assisted systematic search of Medline, PubMed, PsychINFO, SPORTDiscus, CINAHL, CENTRAL, and EMBASE databases was employed to identify all relevant articles related to standing and treadmill desk use. Results Treadmill desks led to the greatest improvement in physiological outcomes including postprandial glucose, HDL cholesterol, and anthropometrics, while standing desk use was associated with few physiological changes. Standing and treadmill desks both showed mixed results for improving psychological well-being with little impact on work performance. Discussion Standing and treadmill desks show some utility for breaking up sitting time and potentially improving select components of health. At present; however, there exist substantial evidence gaps to comprehensively evaluate the utility of each type of desk to enhance health benefits by reducing sedentary time

Risk assessment for physical activity and exercise clearance In pregnant women without contraindications

Traditionally, exercise was advised with caution or not recommended for pregnant women. Women active before pregnancy were advised by physicians to reduce their habitual exercise levels, while previously inactive women were advised to refrain from initiating exercise programs.1 However, guidelines for exercise during pregnancy have evolved substantially during the past 30 years; recommendations have become less restrictive as evidence-based information becomes more readily available.2 Moreover, an increasing number of pregnant women wish to maintain prepregnancy physical fitness levels during the prenatal period, and others wish to initiate exercise for healthier pregnancies.2,3 The conservative nature of medical advice in the past was intended to safeguard the health of both the mother and the growing fetus.2,3 Advice was intentionally conservative because of concern that exercise might shift oxygenated blood and energy substrates away from the fetus to maternal skeletal muscle, as well as increase core body temperature during vulnerable developmental periods such as embryogenesis. Therefore, it was largely unknown whether exercise increased the risk of congenital abnormalities and caused disturbances in optimal fetal growth.2 There were also maternal concerns that excessive exercise might cause conditions such as chronic fatigue and hypoglycemia, or increase the risk of injury (eg, low back pain, musculoskeletal injury).4,5 A more contemporary view of exercise during pregnancy emphasizes that women and their care providers need to consider the risks of not participating in regular physical activities during the prenatal period.3 Previous work in prenatal exercise did not systematically evaluate the prevalence of adverse exercise-related events. This article provides an executive summary of findings from a systematic review of the risks of physical activity for pregnant women without contraindications.6 It is one in a comprehensive series about the risks of physical activity participation in patients with various medical conditions.7 The overall purpose of these systematic reviews was to provide evidence-based recommendations for tools to simplify exercise clearance and prescription: the new Physical Activity Readiness Questionnaire for Everyone (PAR-Q+)8 and the electronic Physical Activity Readiness Medical Examination (ePARmed-X+).9 The purpose of this summary is to present evidence-based information regarding adverse exercise-related events during uncomplicated pregnancy and discuss this information in relation to the family physician’s task of screening patients for physical activity participation

Long-term ultra-marathon running and arterial compliance

Recent reports that habitual marathon runners demonstrate higher levels of stiffness and cardiovascular risk factors have been of great interest to the medical and scientific community. Ultra-marathon running, that is any distance >42.2 km, is increasing in popularity; however, little is known regarding the physiological effects of the sport's unique training and racing practices on vascular health

Arterial compliance decreases following ultra-endurance competition

It is well established that habitual aerobic exercise training is associated with an increase in arterial compliance. A small number of studies have examined the effects of an acute bout of aerobic exercise on measures of arterial compliance, with the conclusion that short duration exercise leads to an increased compliance. However, the response to prolonged ultra-endurance exercise is currently unclear

Characterisation of baroreflex sensitivity of recreational ultra-endurance athletes

Altered autonomic function has been identified following ultra-endurance event participation among elite world-class athletes. Despite dramatic increases in recreational athlete participation in these ultra-endurance events, the physiological effects on these athletes are less known. This investigation sought to characterise changes in surrogate measures of autonomic function: heart rate variability (HRV), blood pressure variability (BPV) and baroreceptor sensitivity (BRS) following ultra-endurance race participation. Further, we sought to compare baseline measures among ultra-endurance athletes and recreationally active controls not participating in the ultra-endurance race. Recreational ultra-endurance athletes (n = 25, 44.6 ± 8.2 years, 8 females) and recreationally active age, sex and body mass index matched controls (n = 25) were evaluated. Measurements of HRV, BPV and BRS were collected pre- and post-race for recreational ultra-endurance athletes and at baseline, for recreationally active controls. Post-race, ultra-endurance athletes demonstrated significantly greater sympathetic modulation [low frequency (LF) power HRV: 50.3 ± 21.6 normalised units (n.u.) to 65.9 ± 20.4 n.u., p = 0.01] and significantly lower parasympathetic modulation [high frequency (HF) power HRV: 45.0 ± 22.4 n.u. to 23.9 ± 13.1 n.u., p < 0.001] and BRS. Baseline measurements BRS (spectral: 13.96 ± 10.82 ms·mmHg−1 vs. 11.39 ± 5.33 ms·mmHg−1) were similar among recreational ultra-endurance athletes and recreationally active controls, though recreational ultra-endurance athletes demonstrated greater parasympathetic modulation of some HRV and BPV measures. Recreational ultra-endurance athletes experienced increased sympathetic tone and declines in BRS post-race, similar to previously reported elite world-class ultra-endurance athletes, though still within normal population ranges