Current Exercise Recommendations Research Articles

Exercise Prescription for Postprandial Glycemic Management.

The detrimental impacts of postprandial hyperglycemia on health are a critical concern, and exercise is recognized a pivotal tool in enhancing glycemic control after a meal. However, current exercise recommendations for managing postprandial glucose levels remain fairly broad and require deeper clarification. This review examines the existing literature aiming to offer a comprehensive guide for exercise prescription to optimize postprandial glycemic management. Specifically, it considers various exercise parameters (i.e., exercise timing, type, intensity, volume, pattern) for crafting exercise prescriptions. Findings predominantly indicate that moderate-intensity exercise initiated shortly after meals may substantially improve glucose response to a meal in healthy individuals and those with type 2 diabetes. Moreover, incorporating short activity breaks throughout the exercise session may provide additional benefits for reducing glucose response.

Exercise to Treat Hypertension: Late Breaking News on Exercise Prescriptions That FITT.

Hypertension is the leading risk factor for cardiovascular disease and an independent predictor of mortality. The prevalence of hypertension has doubled in the last two decades and evidence suggests that almost half the individuals are unaware of their condition. The antihypertensive effects of exercise are now undisputable, and exercise training is recommended by the major professional and scientific societies, including the American College of Sports Medicine (ACSM), as first-line treatment to prevent, treat, and control hypertension. This review aims to overview the evidence supporting the current ACSM Frequency, Intensity, Time, and Type exercise recommendations for hypertension, discuss new and emerging evidence on exercise in the treatment of hypertension from our laboratories; and propose future directions of research integrating this new and emerging evidence.

Exercise During Pregnancy: What Do OB/GYNs Believe and Practice? A Descriptive Analysis.

Introduction: Although regular exercise is recommended during non-complicated pregnancies to promote maternal and fetal/infant health, estimates suggest that only 15% of expectant mothers achieve current exercise recommendations. Although lack of motivation and fear related to potential fetal injury are often cited as reasons for not engaging in regular physical activity/exercise during pregnancy, less is understood about individual attitudes and practice habits of obstetrician and gynecologists (OB/GYNs) regarding exercise recommendations that may influence patient engagement in exercise during pregnancy.Purpose: To describe the attitudes, knowledge, and clinical practice of OB/GYNs regarding exercise during pregnancy.Methods: Surveys were sent via U.S. mail to 950 practicing OB/GYNs identified via publicly available databases. The survey included 11 questions regarding demographic information, exercise physiology knowledge, as well as their attitudes and clinical practice recommendations regarding exercise during pregnancy.Results: One hundred thirty-nine completed surveys were returned (14.6% response rate). Ninety-four percent of physicians surveyed agreed that there are benefits of exercise during pregnancy and/or the benefits of exercise during pregnancy outweigh the risks. Ninety-eight percent of physicians surveyed reported that they (or their medical staff) routinely advise their patients to exercise during pregnancy and 46% reported discussing exercise guidelines related to time, intensity, and type of exercise. Only 13% of physicians surveyed reported taking a semester-long exercise physiology course, yet 27% of physicians surveyed reported developing personalized exercise prescriptions for all (6%) or some (21%) of their patients.Conclusions: Low exercise engagement among expectant mothers does not appear to be due to a lack of guidance or negative views of OB/GYNs regarding exercise during pregnancy.

Moderate-intensity exercise versus high-intensity interval training to recover walking post-stroke: protocol for a randomized controlled trial

BackgroundStroke results in neurologic impairments and aerobic deconditioning that contribute to limited walking capacity which is a major barrier post-stroke. Current exercise recommendations and stroke rehabilitation guidelines recommend moderate-intensity aerobic training post-stroke. Locomotor high-intensity interval training is a promising new strategy that has shown significantly greater improvements in aerobic fitness and motor performance than moderate-intensity aerobic training in other populations. However, the relative benefits and risks of high-intensity interval training and moderate-intensity aerobic training remain poorly understood following stroke. In this study, we hypothesize that locomotor high-intensity interval training will result in greater improvements in walking capacity than moderate-intensity aerobic training.MethodsUsing a single-blind, 3-site randomized controlled trial, 50 chronic (> 6 months) stroke survivors are randomly assigned to complete 36 locomotor training sessions of either high-intensity interval training or moderate-intensity aerobic training. Main eligibility criteria are age 40–80 years, single stroke for which the participant received treatment (experienced 6 months to 5 years prior to consent), walking speed ≤ 1.0 m/s, able to walk at least 3 min on the treadmill at ≥ 0.13 m/s (0.3 mph), stable cardiovascular condition (American Heart Association class B), and the ability to walk 10 m overground without continuous physical assistance. The primary outcome (walking capacity) and secondary outcomes (self-selected and fast gait speed, aerobic fitness, and fatigue) are assessed prior to initiating training and after 4 weeks, 8 weeks, and 12 weeks of training.DiscussionThis study will provide fundamental new knowledge to inform the selection of intensity and duration dosing parameters for gait recovery and optimization of aerobic training interventions in chronic stroke. Data needed to justify and design a subsequent definitive trial will also be obtained. Thus, the results of this study will inform future stroke rehabilitation guidelines on how to optimally improve walking capacity following stroke.Trial registrationClinicalTrials.govNCT03760016. Registered on November 30, 2018.

How effective is an evidence-based exercise intervention in individuals with patellofemoral pain?

ObjectivesGuidelines for a comprehensive rehabilitation programme for patellofemoral pain (PFP) have been developed by international experts. The aim of this study was to analyse the effect of such a rehabilitative exercise programme on pain, function, kinesiophobia, running biomechanics, quadriceps strength and quadriceps muscle inhibition in individuals with PFP. DesignObservational study. SettingClinical environment. ParticipantsTwenty-seven participants with PFP. Main outcome measuresSymptoms [numeric pain rating scale (NPRS)and the pain subscale of the Knee Injury and Osteoarthritis Outcome Score (KOOS)], function measured by using the KUJALA scale and KOOS, kinesiophobia measured by using the Tampa scale, three-dimensional biomechanical running data, quadriceps isometric, concentric and eccentric strength and arthrogenic muscle inhibition (AMI) were acquired before and after the six-week exercise programme. ResultsAlthough pain did not significantly improve all patients were pain-free after the six-week exercise programme (NPRS: p = 0.074). Function, kinesiophobia and quadriceps AMI improved significantly after the six-week exercise programme (KUJALA: p = 0.001, KOOS: p = 0.0001, Tampa: p = 0.017, AMI: p = 0.018). Running biomechanics during stance phase did not change after the exercise intervention. Quadriceps strength was not different after the six-week exercise programme (isometric: p = 0.992, concentric: p = 0.075, eccentric: p = 0.351). ConclusionThe results of this study demonstrate that the current exercise recommendations can improve function and kinesiophobia and reduce pain and AMI in individuals with PFP. There is a need for reconsideration of the current exercise guidelines in stronger individuals with PFP.

Efficacy of High-Intensity Intermittent Training for Improving Cardio-Metabolic Health in Women With Polycystic Ovary Syndrome

Abstract Polycystic ovary syndrome (PCOS) is a common and complex endocrinopathy with significant metabolic and reproductive manifestations, carrying a major health and economic burden. Consistent improvements in clinical outcomes have been reported as a result of exercise training, but shortfalls with exercise prescription are evident. Research suggests that high-intensity intermittent training (HIIT) is feasible, well tolerated and enjoyable for people with or at risk of chronic disease and can address many of the shortfalls and barriers to exercise participation. To investigate the effects of high-intensity exercise on cardio-metabolic health, twenty-four reproductive aged, overweight or obese, sedentary women with PCOS were recruited from the community and randomised to complete either 12 weeks of moderate intensity continuous cycling training (MICT; 60–65% of maximal heart rate [HRmax]; n=11) or HIIT (90–100% HRmax; n=13). All exercise was supervised by an exercise physiologist and completed 3 times per week on a cycle ergometer. Baseline and post-testing measures consisted of peak oxygen consumption (VO2peak) determined by a graded maximal exercise test, body composition by DXA scan and insulin sensitivity determined by euglycaemic-hyperinsulinaemic clamp. Significant improvements in VO2peak were seen after both HIIT (P <0.001) and MICT (P <0.013) with a significant between-group interaction favouring HIIT (P = 0.014). The insulin sensitivity index significantly improved after HIIT (P = 0.009) with no changes observed after MICT (P = 0.860), also resulting in a significant between-group difference favouring HIIT (P = 0.046). No changes were observed for body weight, BMI or fat mass, however, there was a significant increase in percentage of lean mass after HIIT (P = 0.026). The present study is the first to compare current exercise recommendations of moderate and vigorous intensities in women with PCOS. The results of this study provide preliminary validation of HIIT, suggesting that vigorous intensity exercise should be considered in order to improve cardio-metabolic health in women with PCOS.

Multicomponent Home-Based Training Program for Chronic Kidney Disease Patients during Movement Restriction

Both intradialytic and out-of-clinic exercise programs (EP) have been proven to be a safe and effective way to increase fitness levels in end-stage chronic kidney disease (CKD) patients. The actual COVID-19 pandemic situation has forced the suspension of EP offered in hemodialysis centers in many countries; as well as all activities considered as “non-essential” (i.e., sport facilities and fitness centers). Therefore, there is a high risk that movement restrictions would promote physical inactivity and its associated diseases in CKD patients; especially those undergoing domiciliary confinement situations. Given the importance for CKD patients’ overall health to maintain exercise levels and reach physical activity recommendations, the aim of this Protocol was to design a personalized, well-structured, multicomponent physical EP that CKD patients can safely follow at home. We also aimed to provide an initial fitness evaluation tool that allows patients to adapt the EP to their fitness level. Current general exercise recommendations for people living with chronic conditions have been analyzed to develop the present home-based EP proposal.

Remote interventions to improve exercise behaviour in sedentary people living with and beyond cancer: a systematic review and meta-analysis

BackgroundThe COVID-19 pandemic has forced many cancer services to consider a transition to a remote format of delivery that is largely untested. Accordingly, we sought to perform a systematic review of the effects of remotely delivered interventions to improve exercise behaviour in sedentary adults living with and beyond cancer.MethodsEligible studies were randomised controlled trials comparing a remotely delivered exercise intervention to a usual care comparison in sedentary people over 18 years old with a primary cancer diagnosis. Nine electronic databases were searched from inception to November 2020.ResultsThe review included three trials, totalling 186 participants. Two of the included trials incorporated prescriptions that meet current aerobic exercise recommendations, one of which also meets the guidelines for resistance exercise. No trials reported an intervention adherence of 75% or more for a set prescription that meets current exercise guidelines.ConclusionThere is little evidence suggesting that remote exercise interventions promote exercise behaviours or improve physical function in sedentary adults living with and beyond cancer. The development and evaluation of novel remote exercise interventions is needed to establish their usefulness for clinical practice. Given the social response to the COVID-19 pandemic, further research in this area is urgently needed.

Healthy Teleworking: Towards Personalized Exercise Recommendations

Home-based teleworking, associated with sedentary behavior, may impair self-reported adult health status. Current exercise recommendations, based on universal recipes, may be insufficient or even misleading to promote healthy teleworking. From the Network Physiology of Exercise perspective, health is redefined as an adaptive emergent state, product of dynamic interactions among multiple levels (from genetic to social) that cannot be reduced to a few dimensions. Under such a perspective, fitness development is focused on enhancing the individual functional diversity potential, which is better achieved through varied and personalized exercise proposals. This paper discusses some myths related to ideal or unique recommendations, like the ideal exercise or posture, and the contribution of recent computer technologies and applications for prescribing exercise and assessing fitness. Highlighting the need for creating personalized working environments and strengthening the active contribution of users in the process, new recommendations related to teleworking posture, home exercise counselling, exercise monitoring and to the roles of healthcare and exercise professionals are proposed. Instead of exercise prescribers, professionals act as co-designers that help users to learn, co-adapt and adequately contextualize exercise in order to promote their somatic awareness, job satisfaction, productivity, work–life balance, wellbeing and health.

Endurance and Sprint Training Improve Glycemia and V˙O2peak but only Frequent Endurance Benefits Blood Pressure and Lipidemia.

Sprint interval training (SIT) has gained popularity as a time-effective alternative to moderate-intensity endurance training (END). However, whether SIT is equally effective for decreasing cardiometabolic risk factors remains debatable, as many beneficial effects of exercise are thought to be transient, and unlike END, SIT is not recommended daily. Therefore, in line with current exercise recommendations, we examined the ability of SIT and END to improve cardiometabolic health in overweight/obese males. Twenty-three participants were randomized to perform 6 wk of constant workload SIT (3 d·wk-1, 4-6 × 30 s ~170% Wpeak, 2 min recovery, n = 12) or END (5 d·wk-1, 30-40 min, ~60% Wpeak, n = 11) on cycle ergometers. Aerobic capacity (V˙O2peak), body composition, blood pressure (BP), arterial stiffness, endothelial function, glucose and lipid tolerance, and free-living glycemic regulation were assessed pre- and posttraining. Both END and SIT increased V˙O2peak (END ~15%, SIT ~5%) and glucose tolerance (~20%). However, only END decreased diastolic BP, abdominal fat, and improved postprandial lipid tolerance, representing improvements in cardiovascular risk factors that did not occur after SIT. Although SIT, but not END, increased endothelial function, arterial stiffness was not altered in either group. Indices of free-living glycemic regulation were improved after END and trended toward an improvement after SIT (P = 0.06-0.09). However, glycemic control was better on exercise compared with rest days, highlighting the importance of exercise frequency. Furthermore, in an exploratory nature, favorable individual responses (V˙O2peak, BP, glucose tolerance, lipidemia, and body fat) were more prevalent after END than low-frequency SIT. As only high-frequency END improved BP and lipid tolerance, free-living glycemic regulation was better on days that participants exercised, and favorable individual responses were consistent after END, high-frequency END may favorably improve cardiometabolic health.

Abstract 16882: Exercise Prescription Patterns After Spontaneous Coronary Artery Dissection: Insights From a Large Multinational Registry

Introduction: Spontaneous coronary artery dissection (SCAD) is an important cause of myocardial infarction in otherwise healthy and most times presumably fit young women. In the absence of evidence for benefit or harm, exercise prescription (EXP) after SCAD remains arbitrary. We assessed EXP patterns among participants in a large multinational SCAD registry. Methods: Participants with SCAD as confirmed by coronary angiography completed surveys detailing exercise (EX) habits prior to SCAD (initial survey), and EXP from their provider on initial and subsequent visits after SCAD (follow-up survey). Demographic and clinical characteristics were collected by electronic health record review by trained nurse abstractors. EXP was categorized according to EX components that include: type, intensity, frequency, time/session, and external conditions. Results: Among 950 participants, mean ± age was 46.8 ± 9.5 years, 96% were women and 77% reported attending ≥1 Cardiopulmonary Rehabilitation session. Prior to SCAD, 49% were aerobically exercising ≥ 3times per week, and only 32% performed strength-building EX regularly. Initial and subsequent post-SCAD visit details in 299/950 participants showed that most (93%) patients received some form of EX (Figure 1-A) counseling, namely: EXP, unspecific advice or were discouraged from any EX (Figure 1-B) . Limits regarding EX type and intensity were the most common advice received among EXP group (Figure 1-C) . Conclusions: Insights from our study show that only 40% of patients were achieving current exercise recommendations for adults prior to SCAD (vs 53% adult U.S population; CDC, 2018) which suggests that SCAD patients may not be as active as previously described. Most patients receive some form of EX counseling after SCAD; however, a structured EXP is needed to avoid overly cautious approaches that could lead to uncertainty, deconditioning, impaired quality of life, or increase risks associated with a sedentary lifestyle.

High-Intensity Interval Aerobic Resistance Training to Counteract Low Relative Appendicular Lean Soft Tissue Mass in Middle Age: Study Protocol for a Randomized Controlled Trial.

BackgroundSarcopenia is the age-related loss of skeletal muscle mass and function and may exist in early middle age. Previous research in this area has focused on resistance training in older individuals; however, there is a lack of intervention trials in middle-aged adults with low relative appendicular lean soft tissue mass who may be at risk for sarcopenia in older age.ObjectiveThis randomized controlled trial aims to determine the effects of a high-intensity interval aerobic resistance training intervention on appendicular lean soft tissue mass in middle-aged adults with low relative appendicular lean soft tissue mass.MethodsWe will conduct a 40-week, single-blinded randomized controlled trial in 84 middle-aged adults with low appendicular lean soft tissue mass in the wider Dunedin area, New Zealand. We will randomly allocate participants to receive either a group-based, 20-week high-intensity interval aerobic resistance training intervention program or a single, 60-minute education session on current exercise recommendations. After the first 20 weeks, both groups will be given a 20-week home program. The study will assess primary and secondary outcome measures, including body composition (regional and whole-body lean soft tissue mass, fat mass, percentage body fat, measured by dual x-ray absorptiometry), blood biomarkers (cortisol, creatinine, C-reactive protein, lipid profile, hemoglobin), physical fitness (maximum oxygen consumption, blood pressure), physical activity (accelerometry), physical function (handgrip strength, sit-to-stand, gait speed, quadriceps strength), and self-reported questionnaires (health outcomes, self-efficacy, perceived enjoyment of physical activity, and multifactorial lifestyle), at baseline, 20 weeks, and 40 weeks. Physical function and self-reported questionnaires will also be measured at 10 weeks. We will assess the primary outcome measure, total body lean soft tissue mass, at baseline, 20 weeks, and 40 weeks. Analyses will be performed using intention-to-treat principles, comparing the outcomes resulting from the intervention, using linear mixed models.ResultsWe obtained ethical approval for this study from The University of Otago Human Ethics Committee on December 10, 2018. Participant recruitment started on February 11, 2019 and was completed on May 14, 2019. Data collection started on February 25, 2019 and was completed on February 28, 2020. We expect to publish the results in January 2021.ConclusionsHigh-intensity interval aerobic resistance training is a time-efficient form of exercise, enabling busy middle-aged adults to meet physical activity recommendations while maximizing training results. The findings can inform the development of future prevention-focused interventions aimed at counteracting the high prevalence of sarcopenia in the aging population.Trial RegistrationAustralian New Zealand Clinical Trials Registry (ACTRN12618001778279); https://tinyurl.com/y555z6fz.International Registered Report Identifier (IRRID)DERR1-10.2196/22989

Sex differences in exercise efficacy: Is midlife a critical window for promoting healthy cognitive aging?

Dementia is one of the most pressing health care issues of this century. As no curative treatment for dementia exists, research efforts are growing to identify effective lifestyle interventions to prevent or delay onset. One such promising strategy that promotes cognitive and brain health is engaging in physical exercise. However, current exercise recommendations are imprecise. To advance the potential of exercise as a preventative and treatment strategy, important questions regarding moderators (ie, biological sex and age) are being addressed in the literature. Biological sex is recognized as an important variable to consider in exercise efficacy on brain health, with females showing greater cognitive gains. This may be related to sex differences in underlying mechanisms. Here, we argue to better understand the sex differences in exercise efficacy, the timing of exercise intervention should also be considered. Specifically, we present the hypothesis that midlife in females is a critical window for the implementation of exercise as an early intervention to promote brain health and prevent dementia. Further, we speculate that exercise interventions targeting midlife will be of critical importance for the female brain, as females exit this period of the lifespan at greater risk for cognitive impairment. Given the potential sex differences in dementia risk and prevalence, it is imperative to assess potential sex differences in exercise efficacy as an early intervention during midlife.

Predictors of adherence to physical activity guidelines in patients with diabetes mellitus in the US in 2017: An exploratory analysis

AimsTo identify if there is an association between socio-economic or demographic factors, lifestyle habits, or chronic conditions and meeting the current exercise recommendations for adult patients with Diabetes Mellitus 2 in the United States. MethodsThis secondary analysis of a cross sectional study used data from participants who reported having diabetes and answered questions regarding physical activity in the 2017 Behavioral Risk Factor Surveillance System survey (n=37,204; 42% women; 30%<60 years-of-age). Respondents were dichotomized according to physical activity adherence. Predictors tested included socioeconomic and demographic characteristics, lifestyle habits, and chronic conditions. Unadjusted and adjusted logistic regression models were used to calculate odds ratios (OR) and 95% confidence intervals (CI). ResultsOur data showed that 46.5% of participants with diabetes adhered to the physical activity guidelines. Daily smokers were 25% less likely to adhere to the physical activity recommendations (95% CI 0.59–0.95), patients with obesity were 37% less likely (95% CI 0.53–0.74), and those with chronic kidney disease were 24% (95% CI 0.61–0.94) less likely to do so. The odds of adhering to exercise guidelines were reduced by 20% (95% CI 0.70–0.92), 42% (95% CI 0.49–0.68), and 47% (95% CI 0.32–0.57) in good, fair, and poor health respectively. ConclusionPatients with poor health, daily smoking, obesity, or kidney disease may benefit from targeted interventions to accomplish their physical activity recommendations.

SUN-010 Efficacy of High Intensity Intermittent Training for Improving Cardio-Metabolic Health in Women with Polycystic Ovary Syndrome: A Pilot Study

Polycystic ovary syndrome (PCOS) is a common and complex endocrinopathy with reproductive and metabolic manifestations, carrying a major health and economic burden. Exercise training has consistently been found improve clinical outcomes in women with PCOS, but shortfalls with exercise prescription are evident. Research suggests that high intensity intermittent exercise (HIIT) is feasible, well tolerated and enjoyable for people with or at risk of chronic disease and can address many of the shortfalls and barriers to exercise participation. To investigate the effects of high intensity exercise, twenty-four reproductive aged, overweight and obese, previously sedentary women with PCOS were recruited from the community and randomised to complete either 12 weeks of moderate intensity continuous cycling exercise (MOD; 50-60% of maximal heart rate [HRmax]; n=11) or HIIT (90-95% HRmax; n=13). All exercise was supervised by an exercise physiologist and completed 3 times per week on a cycle ergometer. Baseline and post testing measures consisted of peak oxygen consumption (VO2peak) determine by a graded maximal exercise test, insulin sensitivity determined by hyperinsulinaemic-euglycaemic clamp, body composition outcomes and anti-mullerian hormone (AMH). Enjoyment was also measured throughout the intervention using feeling scales. Significant improvements were seen for VO2peak after HIIT with an average increase of 5.6 ± 2.5 mL.kg-1.min-1 (P=0.013) and non-significant increases in the MOD group (3.4 ± 2.1 mL/kg/min; P=0.20). Body composition, fasting insulin and AMH values remained unchanged in both groups. Non-significant improvements in glucose infusion rate (3.3 ± 2.8 mg.lbmkg-1.min-1; P=0.06) and insulin sensitivity index (M-to-I ratio; 3.0 ± 3.8 mg.lbmkg-1.min-1[mU/I]-1 x 100; P=0.17) were found as a result of HIIT compared to no changes after moderate intensity exercise. Importantly, HIIT was also found to be more enjoyable than moderate intensity continuous exercise. The present study is the first to compare current exercise recommendations of moderate and vigorous intensities in women with PCOS. The results of this study provide preliminary validation of HIIT and should be considered for improving cardio-metabolic health in women with PCOS.

Acceptability and Perceived Benefits of Exercise Among Pregnant and Postpartum Women Seeking Psychiatric Care

Background: Exercise may be a potentially helpful strategy to improve mood during the perinatal period. However, little is known about the exercise behaviors and preferences of perinatal women seeking psychiatric care. This study was designed to shed light on the acceptability of exercise-based interventions for this population, and to examine the proportion of perinatal psychiatric patients who report engaging in regular exercise. Materials and Methods: Three hundred perinatal women (31% pregnant, 69% postpartum) seeking psychiatric care completed a survey assessing self-reported exercise behaviors, interest in participating in a perinatal exercise program, and perceived benefits of exercise. Respondents self-reported their presenting psychiatric symptoms and any comorbid health conditions. Results: Fewer than 25% of women surveyed reported any recent exercise, and far less (<9%) reported activity levels consistent with current exercise recommendations. However, 87% reported interest in participating in an exercise program and viewed numerous potential benefits (improved health and energy, sense of accomplishment, better sleep, reduced stress, and less anxiety and depression). More than 65% of women reported significant medical comorbidities; these women were equally interested in exercise programs. Conclusion: In this preliminary study, we found that pregnant and postpartum women seeking psychiatric care reported very low levels of exercise, yet women's interest in participating in a tailored exercise program was high. Findings underscore the potential value of an exercise program for distressed perinatal women. Implementing a tailored exercise program within the context of an existing perinatal care setting could promote access and bode well for initiation and adherence.

The effect of exercise training on blood pressure in African and Asian populations: A systematic review and meta-analysis of randomized controlled trials.

Exercise is key in the primary prevention and management of hypertension. Yet, current exercise recommendations are predominantly based on meta-analyses involving populations of European descent. Since blood pressure (BP) responses to pharmaceutical interventions are known to differ among ethnic groups, we aimed to investigate the BP responses to exercise training in non-European descendants. The aim of this study was to systematically summarize the available literature on the efficacy of exercise on BP in healthy adults (age ≥18 years) of African or Asian origin. We searched the MEDLINE database for randomized controlled trials that evaluated the effect of exercise training on BP in healthy African and Asian adults with optimal BP, elevated BP or hypertension and published in a peer-reviewed journal up to May 2019. Random effect models were fitted to estimate the effect sizes. We identified 22 trials involving individuals of Asian origin (n = 931; mean age: 44 years; 41% male) and four trials involving individuals of African origin (n = 510; mean age: 56.7 years; 80% male). Aerobic exercise training significantly (p < 0.001) reduced systolic and diastolic BP in each ethnic group. Resistance training did not affect the BP of Asian participants with optimal BP. The effect of resistance training in Asians with elevated BP or hypertension and Africans could not be determined due to lack of data. Sub-analyses suggested somewhat larger reductions in systolic BP following aerobic training in hypertensive Africans compared with hypertensive Asians. We found favorable effects of aerobic exercise training on BP in the African and the Asian populations. However, the overall low number of studies and especially the lack of data on resistance training and combined training in African and Asian populations warrant more research to improve the quality of evidence.

Effects of High-Intensity Interval Training Versus Moderate-Intensity Training on Cardiometabolic Health Markers in Individuals With Spinal Cord Injury: A Pilot Study.

Background: Recent studies in nondisabled individuals have demonstrated that low-volume high-intensity interval training (HIIT) can improve cardiometabolic health similar to moderate-intensity training (MIT) despite requiring 20% of the overall time commitment. To date, there have been no studies assessing the effects of HIIT for improving cardiometabolic health in individuals with SCI. Objectives: The primary purpose of this pilot study was to compare the effects of 6 weeks of low-volume HIIT vs MIT using arm crank ergometer exercise to improve body composition, cardiovascular fitness, glucose tolerance, blood lipids, and blood pressure in a cohort of individuals with longstanding SCI. Methods: Participants were randomized to 6 weeks of HIIT or MIT arm crank exercise training. Aerobic capacity, muscular strength, blood lipids, glucose tolerance, blood pressure, and body composition were assessed at baseline and 6 weeks post training. Results: Seven individuals (6 male, 1 female; n = 3 in MIT and n = 4 in HIIT; mean age 51.3 ± 10.5 years) with longstanding SCI completed the study. The preliminary findings from this pilot study demonstrated that individuals with SCI randomized to either 6 weeks of HIIT or MIT displayed improvements in (a) insulin sensitivity, (b) cardiovascular fitness, and (c) muscular strength (p < .05). However, MIT led to greater improvements in arm fat percent and chest press strength compared to HIIT (p < .05). Conclusion: No differences between MIT and HIIT were observed. Both conditions led to improvements in insulin sensitivity, aerobic capacity, muscle strength, and blood lipids in individuals with SCI. Future larger cohort studies are needed to determine if the shorter amount of time required from HIIT is preferable to current MIT exercise recommendations.

Optimization of Exercise Countermeasures for Human Space Flight: Operational Considerations for Concurrent Strength and Aerobic Training.

The physiological challenges presented by space flight and in microgravity (μG) environments are well documented. μG environments can result in declines muscle mass, contractile strength, and functional capabilities. Previous work has focused on exercise countermeasures designed to attenuate the negative effects of μG on skeletal muscle structure, function, and contractile strength and aerobic fitness parameters. Exposure to μG environments influences both strength and aerobic type physical qualities. As such, the current exercise recommendations for those experiencing μG involve a combination of strength and aerobic training or “concurrent training.” Concurrent training strategies can result in development and maintenance of both strength and aerobic capabilities. However, terrestrial research has indicated that if concurrent training strategies are implemented inappropriately, strength development can be inhibited. Previous work has also demonstrated that the aforementioned inhibition of strength development is dependent on the frequency of aerobic training, modality of aerobic training, the relief period between strength and aerobic training, and the intra-session sequencing of strength and aerobic training. While time constraints and feasibility are important considerations for exercise strategies in μG, certain considerations could be made when prescribing concurrent strength and aerobic training to those experiencing human space flight. If strength and aerobic exercise must be performed in close proximity, strength should precede aerobic stimulus. Eccentric strength training methods should be considered to increase mechanical load and reduce metabolic cost. For aerobic capacity, maintenance cycle and/or rowing-based high-intensity intermittent training (HIIT) should be considered and cycle ergometry and/or rowing may be preferable to treadmill running.

Hypothalamic‐Pituitary‐Adrenal Axis Responses to an Acute Bout of Moderate Intensity Aerobic Exercise in Breast Cancer Survivors

The purpose of this investigation was to examine the effect of one 30‐minute bout of moderate intensity aerobic exercise on hypothalamic‐pituitary‐adrenal (HPA) axis hormone responses in women with and without a history of breast cancer. Study participants included 21 women between the ages of 40–75 years, 11 of whom had completed treatments for Stage I–III invasive breast cancer (breast cancer survivors) and 10 of whom did not have a history of cancer diagnosis or treatment (controls). Participants completed a 30‐minute session of aerobic exercise on the cycle ergometer at a workload corresponding to 60% of VO2peak. Blood samples were taken pre‐exercise, immediately post‐exercise, and 30 minutes post‐exercise. Plasma concentrations of corticotropin releasing hormone (CRH), adrenocorticotropic hormone (ACTH), and cortisol were measured at each time point using enzyme‐linked immunosorbent assay (ELISA) techniques (Biotang, Inc., Lexington, MA). Data were compared between groups using Mann‐Whitney U tests and across time using Wilcoxon Signed‐Rank tests. Physical characteristics (e.g. age, height, body mass, BMI, percent body fat and VO2peak) were similar between breast cancer survivors and controls (56 ± 8 years vs. 56 ± 7 years; 163.1 ± 5.3 cm vs. 165.7 ± 5.7 cm; 66.8 ± 9.9 kg vs. 77.0 ± 19.0 kg; 25.1 ± 4.1 kg/m2 vs. 28.1 ± 7.3 kg/m2; 31.1 ± 5.3% vs. 33.4 ± 6.6%; and 21.7 ± 6.8 mL/kg/min vs. 24.3 ± 9.8 mL/kg/min, respectively; p = 0.193–0.973). Cortisol was somewhat elevated immediately post‐exercise in breast cancer survivors relative to controls (Table 1, p = 0.085). CRH decreased significantly at 30 minutes post‐exercise relative to immediately post‐exercise values in breast cancer survivors (Table 1, p= 0.003). ACTH decreased somewhat at 30 minutes post‐exercise relative to immediately post‐exercise values in both groups (p = 0.091 and 0.059 for breast cancer survivors and controls, respectively). All other CRH, ACTH, and cortisol responses were similar between groups and across time (p = 0.114–0.929). These results suggest that one 30‐minute session of moderate intensity aerobic exercise has largely similar effects on hormonal responses of the HPA axis in women with and without a history of breast cancer. These preliminary findings continue to demonstrate that moderate aerobic exercise is well tolerated in breast cancer survivors, thus supporting current exercise recommendations for this population.Support or Funding InformationThis work was supported by Elon University Faculty Research and Development funds.This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.