Establishment of the strong putative relationship between exercise and risk of virtually all non-communicable diseases prompted several research groups over the past two decades to investigate a question of significant public health concern: whether exercise lowers the risk of certain forms of cancer. In this Opinion review I first overview studies of exercise in cancer prevention summarizing evidence from observational studies and available clinical trials. In the final section, I consider the next steps in the continued development of exercise as a cancer prevention strategy.
The scientific interest of exercise medicine for the treatment of cancer is ever expanding. Recently published and updated guidelines for exercise training in cancer patients by the American College of Sports Medicine (ACSM), the Clinical Oncology Society of Australia (COSA) or the Exercise and Sports Science Australia (ESSA) are leading the way towards an individualized approach for exercise prescription. These guidelines provide physicians and therapists with a comprehensive and detailed overview about the beneficial effects of exercise training and, more so, summarize the evidence on potential dose–response mechanisms, including pathways of exercise-induced stimuli to counteract tumour microenvironmental pathologies. However, the most optimal types and doses of exercise training across the cancer disease and treatment continuum are yet to be determined. Therefore, the purpose of this narrative review was to illustrate the current implications but also limitations of exercise training during the different stages of cancer therapy, as well as to discuss necessary future directions. As a second purpose, special attention will be given to the current role of exercise in the treatment of cancer in Germany.
To determine the amount of familiarization sessions required by breast cancer survivors to achieve a reliable measurement of muscle function assessed using isokinetic dynamometry.
Twenty-six breast cancer survivors performed three isokinetic knee extension tests separated by, at least, 48 h. The isokinetic testing protocol included one warm-up set of 10 submaximal knee extensions at 120°/s, followed by two sets of four maximal knee extensions at 60°/s, with 2-min rest interval between sets. Peak torque (PT), time to peak torque (TPT), angle of peak torque (APT), and average power (AP) of each trial was used for the assessment of testing reliability. Percentage change in the mean, typical error, coefficient of variation and intraclass correlation coefficients (ICC2.1) were calculated to determine test–retest reliability.
For PT, change in mean was lower between trials 2 and 3 than between trials 1 and 2 (4.18% and 13.18%, respectively), and ICC was greater between trials 2 and 3 than between trials 1 and 2 (0.962 and 0.818, respectively). For TPT and APT, ICC was clinically acceptable only between trials 2 and 3 (0.757 and 0.803, respectively). For AP, change in mean was clinically acceptable between trials 2 and 3 (9.84%), while ICC met acceptable reliability between both, trials 1 and 2 and, trials 2 and 3 (0.756 and 0.891, respectively).
At least one familiarization session is adequate to achieve reliable measurements of muscle function using isokinetic dynamometry, while avoiding the impact of learning effect of the measurements in breast cancer survivors.
In recent years, the Westernization of dietary habits and increasingly sedentary lifestyle have contributed to a marked increase in the number of type 2 diabetes patients. Sedentary behavior may play a significant role in the development and aggravation of type 2 diabetes. The results of various follow-up studies have demonstrated that proper diet combined with physical exercise is useful in the prevention and treatment of type 2 diabetes. A nationwide survey regarding exercise therapy for diabetes patients in Japan revealed that relatively few physicians provide patients with exercise guidance because of time constraints, that the physicians do not receive additional consultation fee, and that there is a lack of specialized physical exercise educators. Physical exercise promotes the utilization of glucose and free fatty acids in the muscles, and thus lowers blood glucose (BG) levels. Dietary restriction and physical exercise are effective in the prevention and treatment of type 2 diabetes by improving the in vivo sensitivity to insulin. Most adults with diabetes should engage in 150 min or more of moderate-to-vigorous intensity aerobic activity per week, spread out over at least 3 days/week, with no more than two consecutive days without activity. Mild-intensity resistance training such as half squat and calf raise is recommended for elderly individuals who have decreased muscle strength and mass (sarcopenia). Prolonged sitting should be interrupted every 30 min for BG benefits, particularly in adults with type 2 diabetes. Individuals with type 2 diabetes are also encouraged to increase their total daily unstructured physical activity (daily movement).
Children require 9–11 h sleep to ensure adequate growth and development by optimizing the efficiency of a number of biological systems, including the cardiovascular system. The study aim was to determine whether short sleep duration (< 9 h) is associated with elevated aortic arterial stiffness in children aged 9–11 years, independent of other lifestyle behaviors, including physical activity, sedentary behaviour and dietary patterns.
This cross-sectional study included 421 children (51% female) aged 9–11 years. Aortic arterial stiffness was measured using carotid-femoral pulse wave velocity (cfPWV), sleep duration, time spent sedentary, and moderate-vigorous physical activity were measured using wrist actigraphy, and dietary patterns using a food frequency questionnaire. Associations between short sleep duration and cfPWV were examined using mixed effects regression.
There was a positive [unadjusted] association between short sleep duration and cfPWV (β = 0.245, 95% CI 0.093–0.396). This association persisted following adjustment for demographic factors and was strengthened following adjustment for lifestyle behaviors (β = 0.331, 95% CI 0.109–0.553).
Short sleepers (< 9 h) had a clinically meaningful elevated aortic arterial stiffness in comparison to those sleeping the recommended daily 9–11 h. Sleep duration may be important for cardiovascular health independent of other lifestyle behaviors.
During aging, the skeletal muscle tissue is one of the most affected, undergoing loss of mass and function, a process defined as sarcopenia. This age-related muscle mass and function decline, dependent on many factors, predispose individuals to decreased mobility, reduced muscle power and increased risk of falls. Several factors at the cellular and molecular level affect muscle aging, synergizing with each other. At present, it is broadly accepted that Reactive Oxygen Species (ROS) play a primary role in the aging process, especially in those tissues like skeletal muscle, where the generation of free radicals is more pronounced as a consequence of the high consumption of oxygen. Recently, several studies have highlighted the involvement of muscle stem cells (satellite cells, SCs) in the progression of sarcopenia, showing a concomitant regression of activity and number of these cells. At a sub-cellular level, the main processes correlated with sarcopenia are the alteration of protein synthesis and mitochondrial dysfunction. Attempts to slow down or revert sarcopenia are essentially based on three approaches: use of supplements, pharmaceutical therapies and physical activity. In brief, it seems that appropriate physical exercise training protocols could be capable of slowing down and sometimes reversing the sarcopenic process. This finding is the consequence of a beneficial action of physical exercise on mitochondria and/or on the regenerative process led by SCs with different effects on the basis of training characteristics. Furthermore, according to a recent hypothesis, early strength training should be considered as public health advice.
Approximately, one-third of individuals who sustain an anterior cruciate ligament (ACL) injury and undergo ACL reconstruction develop radiographic posttraumatic osteoarthritis within one decade of injury. Traditional ACL reconstruction and therapeutic rehabilitation do not reduce the risk of developing posttraumatic osteoarthritis compared to individuals who do not elect to undergo ACL reconstruction. Currently, there is no cure for posttraumatic osteoarthritis; therefore, prevention of posttraumatic osteoarthritis following ACL injury and reconstruction is paramount for maintaining long-term joint health following injury. The purpose of the current clinical commentary is to review the overall global burden of knee osteoarthritis and further explain the risk of posttraumatic osteoarthritis following ACL injury and reconstruction, as well as outlining current methods for detecting joint tissue changes that may be indicative of early posttraumatic osteoarthritis following ACL injury. Finally, we review current concepts for managing the risk of posttraumatic osteoarthritis development following ACL injury and reconstruction. The overall goal of the current review is to provide sports medicine clinicians with knowledge to help improve the long-term health of patients with traumatic knee injuries.
Inter-limb coordination may provide insight into why patients with anterior cruciate ligament reconstructive surgery (ACLR) have an increased risk for future injury and osteoarthritis. The purpose of this study was to compare inter-limb coordination prior-to anterior cruciate ligament (ACL) injury and following ACLR.
Unilateral lower extremity biomechanics during a double-leg jump landing were collected prior-to ACL injury (baseline) and after ACLR, rehabilitation, and return to physical activity (follow-up). Sixty-nine participants were included in this analysis: 31 participants suffered an ACL injury since baseline: 12 injured the leg tested at baseline [ACLR-injured leg (ACLR-INJ), n = 12] and 19 injured the leg that was not tested at baseline [ACLR-uninjured leg (ACLR-UNINJ) n = 19]; 38 participants served as matched controls. Inter-limb coordination—calculated as the mean coupling angle—between the hip and knee were measured in the respective leg of each defined group and compared amongst groups at baseline and follow-up.
We observed no significant change in sagittal or frontal plane inter-limb coordination amongst groups or across time (P > 0.05). A significant decrease in inter-limb coordination in the transverse plane from baseline and follow-up was observed but limited to the ACLR-INJ group (P = 0.016).
The primary finding of this study is that inter-limb coordination between the hip and knee in the sagittal and frontal plane is unchanged by ACL injury and ACLR. This may help explain previous observations of changes in kinematics at both the hip and knee in this population. Our observation of alterations in the transverse plane should be interpreted with caution, but may provide additional evidence for potential mechanisms that lead to the development of osteoarthritis in ACLR patients.