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Objectives Usual physical activity (PA) is a complex exposure and typical instruments to measure aspects of PA are subject to measurement error, from systematic biases and biological variability. This error can lead to biased estimates of associations between PA and health outcomes. We developed a calibrated physical activity measure that adjusts for measurement error in both self-reported and accelerometry measures of PA in adults from the US Hispanic Community Health Study/Study of Latinos (HCHS/SOL), a community-based cohort study. Design Total energy expenditure (TEE) from doubly labeled water and resting energy expenditure (REE) from indirect calorimetry were measured in 445 men and women aged 18–74 years in 2010–2012, as part of the HCHS/SOL Study of Latinos: Nutrition & Physical Activity Assessment Study (SOLNAS). Measurements were repeated in a subset (N = 98) 6 months later. Method Calibration equations for usual activity-related energy expenditure (AEE = 0.90 × TEE-REE) were developed by regressing this objective biomarker on self-reported PA and sedentary behavior, Actical accelerometer PA, and other subject characteristics. Results Age, weight and height explained a significant amount of variation in AEE. Actical PA and wear-time were important predictors of AEE; whereas, self-reported PA was not independently associated with AEE. The final calibration equation explained fifty percent of variation in AEE. Conclusions The developed calibration equations can be used to obtain error-corrected associations between PA and health outcomes in HCHS/SOL. Our study represents a unique opportunity to understand the measurement characteristics of PA instruments in an under-studied Hispanic/Latino cohort.

Objectives To evaluate the current level of physical activity (PA) training provided to Australian medical students. Design Individual interviews were completed via phone interview or online survey from June–October 2015. Methods Program leaders from Australian medical schools, who were knowledgeable about their curriculum content, were invited to participate in the study. The number of programs, hours of PA training instruction, institutional attitude towards offering PA, barriers experienced, and content areas in which PA training was offered, were explored. Results Seventeen of the 19 (89%) Australian medical schools participated in the study. Among the responding schools, 15 (88.2%) reported providing specific PA training to medical students. Thirteen of these 15 schools (86.7%) taught the national aerobic guidelines while only seven (46.7%) taught the national strength training recommendations. Four, five, and six year programs reported providing an average of 6.6, 5.0, and 12.3 h of PA training, respectively, across their entire curriculum. Only 42.9% of the schools that had PA training reported that it was sufficient for their medical students. Nearly half (41.2%) of the respondents reported no barriers to implementing PA training into their medical curricula. Conclusions Most Australian medical schools reported including some PA training in their medical curriculum. Key topics, such as the national strength recommendations, however, were not taught by most schools. Given the importance of PA for the prevention and treatment of numerous mental and physical health outcomes, it is unlikely that the attention it currently receives adequately prepares medical students to treat patients.

Background A third of the world's population does not engage in recommended levels of physical activity (PA), leading to substantial health and economic burdens. The healthcare sector offers a variety of resources that can help counsel, refer and deliver PA promotion programmes for purposes of primordial, primary, secondary and tertiary prevention. Substantial evidence already exists in support of multipronged PA counselling, prescription and referral strategies, in particular those linking healthcare and community-based resources. Methods The Exercise is Medicine (EIM) initiative was introduced in 2007 to advance the implementation of evidence-based strategies to elevate the status of PA in healthcare. In this article, we describe the evolution and global expansion of the EIM initiative, its components, their implementation, an evaluation framework and future initiative activities. Results Until now, EIM has a presence in 39 countries with EIM Regional Centers established in North America, Latin America, Europe, Africa, Southeast Asia, China and Australasia. The EIM Global Health Initiative is transitioning from its initial phase of infrastructure and awareness building to a phase of programme implementation, with an emphasis in low-to-middle income countries, where 80% of deaths due to non-communicable diseases already occur, but where a large gap in research and implementation of PA strategies exists. Conclusions Broad implementation of PA counselling and referral systems, as clinical practice standard of care, has the potential to improve PA at the population level by complementing and leveraging other efforts and to contribute to achieving global targets for the reduction of inactivity and related morbidity and mortality.

Context:There are numerous ways to overload the scapular stabilizers.Objectives:To assess scapular stabilizer activity using the Bodyblade® and other traditional training devices.Design:Repeated measures analysis of surface EMG data collected from the upper trapezius (UT), lower trapezius (LT), and serratus anterior (SA) during shoulder flexion and abduction using Bodyblade®, cuff weight, and Thera-Band® resistance.Setting:Laboratory.Participants:Thirty collegiate athletes (20.0 ± 1.7 years).Intervention:Participants performed 10 repetitions of shoulder flexion and abduction.Main Outcome Measures:For each movement, normalized root mean square values (NrmsEMG) were computed for each muscle during each repetition under each training condition. Data were analyzed using 3 (condition) × 10 (repetition) repeated measures ANOVAs.Results:During shoulder flexion and abduction, the NrmsEMG of the UT, LT, and SA were significantly greater when using the Bodyblade® than the Thera-Band® or cuff weight.Conclusion:The Bodyblade® produces greater scapular activity than traditional resistance techniques.

Background: Medical professionals serve as influential sources of information and guidance for their patients. Medical school may be an opportune time to provide future physicians with training in physical activity (PA) so that it can be more effectively addressed in clinical practice. Methods: To assess the inclusion and amount of PA training in US medical school curricula, we attempted to conduct structured interviews with the program directors of the 171 accredited US medical education programs in the spring of 2013. Results: Seventy-four schools (allopathic, n = 64; osteopathic, n = 10) completed the structured interviews. Fifty-eight programs (78.4%) reported having PA training included as a part of their curriculum. Thirty-five (61.4%) and 25 (43.9%) programs included instruction on national aerobic and strength training guidelines, respectively. Thirty-one programs (56.4%) felt that they offered a sufficient level of PA-related training for their students to successfully counsel their patients in the future. Over the 4 years of medical school, an average of 8.1 (± 9.8) h of mandatory PA training was offered. Conclusion: Though many medical schools report providing some level of PA content, the time dedicated for this training is still low in comparison to other topics, such as nutrition education, which are featured more prominently. New and innovative ideas are needed for the integration of more, higher quality PA training for our next generation of medical practitioners.

Leg extension (LE) is commonly used to strengthen the quadriceps muscles during training and rehabilitation. This study examined the effects of limb position (POS) and range of motion (ROM) on quadriceps electromyography (EMG) during 8 repetitions (REP) of LE. Twenty-four participants performed 8 LE REP at their 8 repetition maximum with lower limbs medially rotated (TI), laterally rotated (TO), and neutral (NEU). Each REP EMG was averaged over the first, middle, and final 0.524 rad ROM. For vastus medialis oblique (VMO), a REP × ROM interaction was detected (p < 0.02). The middle 0.524 rad produced significantly higher EMG than the initial 0.524 rad for REP 6-8 and the final 0.524 rad produced higher EMG than the initial 0.524 rad for REP 1, 2, 3, 4, 6, and 8 (p ≤ 0.05). For rectus femoris (RF), EMG activity increased across REP with TO generating the greatest activity (p < 0.001). For vastus lateralis (VL), EMG increased across REP (p < 0.001) with NEU and TO EMG increasing linearly throughout ROM and TI activity greatest during the middle 0.524 rad. We conclude that to target the VMO, the optimal ROM is the final 1.047 rad regardless of POS, while maximum EMG for the RF is generated using TO regardless of ROM. In contrast, the VL is maximally activated using TI over the first 1.047 rad ROM or in NEU over the final 0.524 rad ROM.

This study investigated variations in electromyographic (EMG) responses of the vastus lateralis (VL), rectus femoris (RF), and vastus medialis (VM) due to foot position during leg extension. Twenty-four men and women (23.67 +/= 4.02 years) performed 8 repetitions at 70% of 8 repetition maximum with their leg medially rotated, laterally rotated, and neutral. Repeated-measures analyses of variance indicated that the highest normalized root mean square (NrmsEMG) for the VM and VL occurred with medial rotation, and the highest NrmsEMG for the RF occurred with lateral rotation. Significant NrmsEMG increases and median power frequency decreases occurred across repetitions regardless of foot position. Therefore, medial rotation produced the greatest muscle activation for the VL and VM, whereas lateral rotation produced the greatest activation in the RF. These findings are applicable to athletes or bodybuilders who are seeking to selectively increase either the size or performance of a specific muscle of the quadriceps group.

Tennis requires skill, physical attributes, and strategy. Ball velocity and placement are two of the most important components in winning the faster-paced modern game. Although isokinetic testing has been used to evaluate physical characteristics and injury potential in tennis players, few studies have compared isokinetics and on-court performance. Such a comparison would help establish links between speed-specific properties of functioning muscles and stroke production and could affect overall training strategy. This study compared isokinetic peak torque (PT), average power (AP), and total work (TW) during specific testing patterns correlated with ball velocity or stroke accuracy during the service, forehand, and backhand and developed predictive equations for each stroke using these variables. Thirty-five players, aged 13-18 years with at least 4 years playing experience, were evaluated using internal and external shoulder rotation, leg extension, and diagonal throwing motions. Ball velocity was measured using a radar gun. Accuracy was evaluated on the basis of shot position and depth. Significant correlations were found between ball velocity and a number of isokinetic variables, while no significant correlations were observed with shot accuracy. Significant isokinetic variables for each stroke were entered into regression models. One isokinetic speed sufficiently predicted ball velocity for each stroke, since no increase in predictive capacity was observed with the addition of other isokinetic parameters. We conclude that isokinetics at testing speeds between 1.57 and 4.71 rad.s(-1) can effectively predict ball velocity, but not accuracy, and that our results may be helpful in planning strategies for training and rehabilitation.

This study investigated variations in electromyographic (EMG) responses of the erector spinae (ES), vastus medialis (VM), rectus femoris (RF), and vastus lateralis (VL) to different seatback angles during leg extension. Twenty men and women (10 men, 10 women; age 27.49 +/- 6.16 years) performed 8 repetitions at 70% of 8 repetition maximum at seatback angles of 1.57, 1.75, and 1.92 radius (rad). Analyses using repeated-measures analysis of variance indicated the greatest root square mean of the EMG (rmsEMG) and integrated EMG (intEMG) for the ES were at 1.92 rad, and the greatest for the VM (concentric) and VL (eccentric) were at 1.57 rad. No differences were observed among seat angles for the RF except for a higher normalized intEMG at 1.92 than 1.75 rad (concentric). Throughout all sets for all conditions and muscles, rmsEMG and intEMG significantly increased and median power frequency significantly decreased. These data indicate that a seatback angle of 1.57 rad is best for a leg extension machine, because this angle maximizes quadriceps activity while minimizing stress on the lower back muscles.

Background The mechanisms through which exercise reduces cardiovascular disease are not fully understood. We used echocardiograms, cardiac biomarkers and gene expression to investigate cardiovascular effects associated with exercise training. Methods Nineteen sedentary men (22–37 years) completed a 17-week half-marathon training program. Serial measurements of resting heart rate, blood pressure, maximum oxygen consumption, lipids, C-reactive protein, cardiac troponin T, echocardiograms and blood for gene expression were obtained from baseline to peak training. Controls included 22 sedentary men who did not exercise. Results Among the training group, VO2 max increased from 37.1 to 42.0 ml/kg/min (p 2 max identified loci that differentiated these two groups at baseline and after training. Conclusion Intensive exercise training leads to significant increase in cardiac and hemodynamic performance, and significant changes in expression of genes involved in immune and inflammatory response.