Changes in Bone Biomarkers, BMC, and Insulin Resistance Following a 10-Week Whole Body Vibration Exercise Program in Overweight Latino Boys.

PURPOSE: With the childhood obesity epidemic, efficient methods of exercise are sought to improve health. We tested whether whole body vibration (WBV) exercise can positively affect bone metabolism and improve insulin/glucose dynamics in sedentary overweight Latino boys. METHODS: Twenty Latino boys 8-10 years of age were randomly assigned to either a control (CON) or 3 days/wk WBV exercise (VIB) for 10-wk. RESULTS: Significant increases in BMC (4.5 ± 3.2%; p=0.01) and BMD (1.3 ± 1.3%; p<0.01) were observed for the VIB group when compared to baseline values. For the CON group BMC significantly increased (2.0 ± 2.2%; p=0.02), with no change in BMD (0.8 ± 1.3%; p=0.11). There were no significant between group changes in BMC or BMD. No significant change was observed for osteocalcin and (collagen type I C-telopeptide) CTx for the VIB group. However, osteocalcin showed a decreasing trend (p=0.09) and CTx significantly increased (p<0.03) for the CON group. This increase in CTx was significantly different between groups (p<0.02) and the effect size of between-group difference in change was large (-1.09). There were no significant correlations between osteocalcin and measures of fat mass or insulin resistance for collapsed data. CONCLUSION: Although bone metabolism was altered by WBV training, no associations were apparent between osteocalcin and insulin resistance. These findings suggest WBV exercise may positively increase BMC and BMD by decreasing bone resorption in overweight Latino boys.

Short rest interval lengths between sets optimally enhance body composition and performance with 8 weeks of strength resistance training in older men.

PURPOSE: To determine if 8 weeks of periodized strength resistance training (RT) utilizing relatively short rest interval lengths (RI) in between sets (SS) would induce greater improvements in body composition and muscular performance, compared to the same RT program utilizing extended RI (SL). METHODS: 22 male volunteers (SS: n = 11, 65.6 ± 3.4 years; SL: n = 11, 70.3 ± 4.9 years) were assigned to one of two strength RT groups, following 4 weeks of periodized hypertrophic RT (PHRT): strength RT with 60-s RI (SS) or strength RT with 4-min RI (SL). Prior to randomization, all 22 study participants trained 3 days/week, for 4 weeks, targeting hypertrophy; from week 4 to week 12, SS and SL followed the same periodized strength RT program for 8 weeks, with RI the only difference in their RT prescription. RESULTS: Following PHRT, all study participants experienced increases in lean body mass (LBM) (p < 0.01), upper and lower body strength (p < 0.001), and dynamic power (p < 0.001), as well as decreases in percentage body fat (p < 0.05). Across the 8-week strength RT phase, SS experienced significantly greater increases in LBM (p = 0.001), flat machine bench press 1-RM (p < 0.001), bilateral leg press 1-RM (p < 0.001), narrow/neutral grip lat pulldown (p < 0.01), and Margaria stair-climbing power (p < 0.001), compared to SL. CONCLUSIONS: This study suggests 8 weeks of periodized high-intensity strength RT with shortened RI induces significantly greater enhancements in body composition, muscular performance, and functional performance, compared to the same RT prescription with extended RI, in older men. Applied professionals may optimize certain RT-induced adaptations, by incorporating shortened RI.

Randomized controlled trial to evaluate the effects of combined progressive exercise on metabolic syndrome in breast cancer survivors: rationale, design, and methods.

BACKGROUND: Metabolic syndrome (MetS) is increasingly present in breast cancer survivors, possibly worsened by cancer-related treatments, such as chemotherapy. MetS greatly increases risk of cardiovascular disease and diabetes, co-morbidities that could impair the survivorship experience, and possibly lead to cancer recurrence. Exercise has been shown to positively influence quality of life (QOL), physical function, muscular strength and endurance, reduce fatigue, and improve emotional well-being; however, the impact on MetS components (visceral adiposity, hyperglycemia, low serum high-density lipoprotein cholesterol, hypertriglyceridemia, and hypertension) remains largely unknown. In this trial, we aim to assess the effects of combined (aerobic and resistance) exercise on components of MetS, as well as on physical fitness and QOL, in breast cancer survivors soon after completing cancer-related treatments. METHODS/DESIGN: This study is a prospective randomized controlled trial (RCT) investigating the effects of a 16-week supervised progressive aerobic and resistance exercise training intervention on MetS in 100 breast cancer survivors. Main inclusion criteria are histologically-confirmed breast cancer stage I-III, completion of chemotherapy and/or radiation within 6 months prior to initiation of the study, sedentary, and free from musculoskeletal disorders. The primary endpoint is MetS; secondary endpoints include: muscle strength, shoulder function, cardiorespiratory fitness, body composition, bone mineral density, and QOL. Participants randomized to the Exercise group participate in 3 supervised weekly exercise sessions for 16 weeks. Participants randomized to the Control group are offered the same intervention after the 16-week period of observation. DISCUSSION: This is the one of few RCTs examining the effects of exercise on MetS in breast cancer survivors. Results will contribute a better understanding of metabolic disease-related effects of resistance and aerobic exercise training and inform intervention programs that will optimally improve physiological and psychosocial health during cancer survivorship, and that are ultimately aimed at improving prognosis. TRIAL REGISTRATION: NCT01140282; REGISTRATION: June 10, 2010.

Periodized resistance training with and without supplementation improve body composition and performance in older men.

PURPOSE: To examine the effects of 12 weeks of periodized resistance training (RT) with and without combined creatine and whey protein supplementation on changes in body composition, muscular strength, and functional performance. METHODS: Twenty-two male volunteers (68.1 ± 6.1 years) were randomly assigned to one of three groups: RT plus supplementation (RTS, n = 7); RT only (RT, n = 7); or control (C, n = 8). RTS consumed 0.3 g/kg/day of creatine for 5 days followed by 0.07 g/kg/day. RTS also consumed one 35 g liquid protein ready-to-drink daily. RT and RTS trained 3 days/week. RESULTS: Following 12 weeks of training, there were no significant differences in the main measured outcome variables between RT and RTS. RTS increased relative (% change) lean body mass (LBM, 3.3 ± 3.1 %) compared with C (p = 0.01). Compared to baseline, RT increased LBM at week 6 (60.2 ± 8.3 to 61.6 ± 9.4 kg; p < 0.05), and decreased fat mass (20.8 ± 4.2 to 19.0 ± 3.9 kg; p = 0.05) and percentage body fat at week 12 (25.7 ± 3.8 to 23.8 ± 4.0 %; p = 0.05); RTS increased LBM at week 6 (p < 0.01) and week 12 (56.4 ± 4.3 to 58.2 ± 3.4 kg; p < 0.01), and decreased percentage body fat at week 12 (23.9 ± 4.4 to 22.0 ± 4.4 %; p < 0.01). In addition, compared to C, relative bench press 1-RM increased for RTS (72.4 ± 62.2 %; p < 0.01) and RT (50.1 ± 21.5 %; p = 0.05); relative leg press 1-RM increased for RTS (129.6 ± 39.4 %; p < 0.0001) and RT (112.9 ± 22.7 %; p < 0.0001); RTS increased relative Margaria stair-climbing power (38.3 ± 30.4 %; p < 0.05); and, relative 400-m walk time decreased for RT (-11 ± 9.2 %; p < 0.05) and RTS (-9.6 ± 9.4 %; p = 0.05). RT increased estimated VO2Max at week 6 (p < 0.01) and 12 (34.6 ± 1.9 to 36.4 ± 2.7 ml/kg/min; p = 0.01) compared to baseline. Lastly, RTS increased estimated VO2Max at week 12 (36.3 ± 2.7 to 37.5 ± 3.3 ml/kg/min; p = 0.05) compared to baseline. CONCLUSION: Creatine and whey protein supplementation may not provide additional benefits in older adults performing periodized RT to augment muscular and functional performance.

Randomized control trial to evaluate the effects of acute testosterone administration in men on muscle mass, strength, and physical function following ACL reconstructive surgery: rationale, design, methods.

BACKGROUND: The anterior cruciate ligament (ACL) is one of four major ligaments in the knee that provide stability during physical activity. A tear in the ACL is characterized by joint instability that leads to decreased activity, knee dysfunction, reduced quality of life and a loss of muscle mass and strength. While rehabilitation is the standard-of-care for return to daily function, additional surgical reconstruction can provide individuals with an opportunity to return to sports and strenuous physical activity. Over 200,000 ACL reconstructions are performed in the United States each year, and rehabilitation following surgery is slow and expensive. One possible method to improve the recovery process is the use of intramuscular testosterone, which has been shown to increase muscle mass and strength independent of exercise. With short-term use of supraphysiologic doses of testosterone, we hope to reduce loss of muscle mass and strength and minimize loss of physical function following ACL reconstruction compared to standard-of-care alone. METHODS/DESIGN: This study is a double-blinded randomized control trial. Men 18-50 years of age, scheduled for ACL reconstruction are randomized into two groups. Participants randomized to the testosterone group receive intramuscular testosterone administration once per week for 8 weeks starting 2 weeks prior to surgery. Participants randomized to the control group receive a saline placebo intramuscularly instead of testosterone. Lean mass, muscle strength and physical function are measured at 5 time points: 2 weeks pre-surgery, 1 day pre-surgery, and 6, 12, 24 weeks post-surgery. Both groups follow standard-of-care rehabilitation protocol. DISCUSSION: We believe that testosterone therapy will help reduce the loss of muscle mass and strength experienced after ACL injury and reconstruction. Hopefully this will provide a way to shorten the rehabilitation necessary following ACL reconstruction. If successful, testosterone therapy may also be used for other injuries involving trauma and muscle atrophy. TRIAL REGISTRATION: NCT01595581, REGISTRATION: May 8, 2012.

The role of transcutaneous electrical nerve stimulation for menstrual pain relief: A randomized control trial.

BACKGROUND: Abdominal pain due to menses (primary dysmenorrhea) is an extremely pervasive and debilitating symptom affecting up to 90% of menstruating individuals. OBJECTIVE: The objective of this randomized control trial was to investigate the effect of a commercial transcutaneous electrical nerve stimulation unit, Therabody PowerDot® (Therabody Inc., Los Angeles) on dysmenorrhea compared with non-steroidal anti-inflammatory drug use. DESIGN: This was a randomized cross-over study. METHODS: A total of 47 participants agreed to participate in the study, with 34 completing it. Participants completed treatments across three consecutive menstrual cycles in randomized order: single-unit transcutaneous electrical nerve stimulation (Uno), dual unit transcutaneous electrical nerve stimulation (Duo), and non-steroidal anti-inflammatory drug use (Control). Upon onset of dysmenorrhea, participants applied transcutaneous electrical nerve stimulation to their abdomen for a minimum of 30 min. Control participants were instructed to take non-steroidal anti-inflammatory drugs as needed. Surveys were used to record pain before and after treatment. We hypothesized that the PowerDot would decrease self-reported pain scores, and decrease non-steroidal anti-inflammatory drug consumption during menses. RESULTS: Participants experienced a statistically and clinically significant reduction in pain during the Control (-3.52 ± 1.9), Uno (-2.10 ± 1.6), and Duo (-2.19 ± 1.7) cycles (p < 0.001). The doses of non-steroidal anti-inflammatory drugs consumed during the Control cycle (3.5 ± 2.6), was significantly different as compared with that of Uno (1.5 ± 3.0), or Duo (1.1 ± 2.6) (p = 0.004). CONCLUSIONS: Use of a commercial transcutaneous electrical nerve stimulation unit results in significant decrease in pain. Although not as robust as the relief in pain induced by non-steroidal anti-inflammatory drugs, the adverse events of transcutaneous electrical nerve stimulation are minimal in comparison. Therefore, transcutaneous electrical nerve stimulation appears to be a viable alternative to pain relief from dysmenorrhea. CLINICAL TRIAL REGISTRATION: NCT05178589.

The role of electrical signals for period pain reliefMenstruation, also known as the period, is a cyclicly occurring event in people who are assigned female at birth. Often, the period is associated with abdominal pain that can be debilitating for many. This abdominal pain is typically treated using over-the-counter medications, such as ibuprofen; however, there several noted side effects that can arise from use of such medication. As such, this study aimed to understand if a device (Therabody PowerDot^®; Therabody Inc., Los Angeles) that sends an electrical current to pads placed over the abdomen, much like a heating pad, could be used to decrease pain during the period to a similar level as medication. The research team studied three consecutive periods with differing setups: a single, elongated pad, placed on the lower abdomen (Uno), two circular pads placed on the lower abdomen (Duo), or no use of the device, only medication (Control). The researchers analyzed data from 34 individuals. It was found that all three cycles experienced a significant decrease in pain, with the control cycle having a greater decrease in pain than both the Uno and Duo. This study suggests that the electrical stimulation used here can greatly decrease pain during the period, though not as substantial as medication.

Initial development of skill with a reversed bicycle and a case series of experienced riders.

Riding a bicycle is considered a durable skill that cannot be forgotten. Here, novice participants practiced riding a reversed bicycle, in which a reversing gear inverted the handlebar's rotation. Although learning to ride the reversed bicycle was possible, it was slow, highly variable, implicit, and followed an S-shape pattern. In the initial learning phase, failed attempts to ride the normal bicycle indicated strong interference between the two bicycle skills. While additional practice decreased this interference effect, a subset of learners could not ride either bicycle after eight sessions of practice. Experienced riders who performed extensive practice could switch bicycles without failed attempts and exhibited similar performance (i.e., similar handlebar oscillations) on both bicycles. However, their performance on the normal bicycle was worse than that of the novice bicycle riders at baseline. In conclusion, "unlearning" of the normal bicycle skill precedes the initial learning of the reversed bicycle skill, and a signature of such unlearning is still present following extensive practice.

Value of measuring muscle performance to assess changes in lean mass with testosterone and growth hormone supplementation.

We hypothesized that treatment with testosterone (T) and recombinant human growth hormone (rhGH) would increase lean mass (LM) and muscle strength proportionally and an in a linear manner over 16 weeks. This was a multicenter, randomized, controlled, double-masked investigation of T and rhGH supplementation in older (71 ± 4 years) community-dwelling men. Participants received transdermal T at either 5 or 10 g/day as well as rhGH at 0, 3.0 or 5.0 µg/kg/day for 16 weeks. Body composition was determined by dual-energy X-ray absorptiometry (DEXA) and muscle performance by composite one-repetition maximum (1-RM) strength and strength per unit of lean mass (muscle quality, MQ) for five major muscle groups (upper and lower body) at baseline, week 8 and 17. The average change in total LM at study week 8 compared with baseline was 1.50 ± 1.54 kg (P < 0.0001) in the T only group and 2.64 ± 1.7 (P < 0.0001) in the T + rhGH group and at week 17 was 1.46 ± 1.48 kg (P < 0.0001) in the T only group and 2.14 ± 1.96 kg (P < 0.0001) in the T + rhGH group. 1-RM strength improved modestly in both groups combined (12.0 ± 23.9%, P < 0.0001) at week 8 but at week 17 these changes were twofold greater (24.7 ± 31.0%, P < 0.0001). MQ did not significantly change from baseline to week 8 but increased for the entire cohort, T only, and T + rhGH groups by week 17 (P < 0.001). Despite sizeable increases in LM measurements at week 8, tests of muscle performance did not show substantive improvements at this time point.

Influence of rest interval length on acute testosterone and cortisol responses to volume-load-equated total body hypertrophic and strength protocols.

We hypothesized that total body strength (S) and hypertrophic (H) resistance training (RT) protocols using relatively short rest interval (RI) lengths between sets will elicit significant acute increases in total testosterone (TT) and cortisol (C) in healthy young men. Six men, 26 (±2.4) years, completed 4 randomized RT sessions, after a control session (R). The S and H protocols were equated for volume load (sets × repetitions × load); S: 8 sets × 3 repetitions at 85% 1RM, H: 3 sets × 10 repetitions at 70% 1RM, for all exercises. The RI used 60 seconds (S60, H60) and 90 seconds (S90, H90). Blood was drawn preexercise (PRE), immediately postexercise (POST), 15 minutes postexercise (15 MIN), and 30 minutes postexercise (30 MIN). The H60 elicited significant increases in TT from PRE (7.32 ± 1.85 ng·ml) to POST (8.87 ± 1.83 ng·ml(-1)) (p < 0.01), 15 MIN (8.58 ± 2.15 ng·ml(-1)) (p < 0.01), and 30 MIN (8.28 ± 2.16 ng·ml(-1)) (p < 0.05). The H90 also elicited significant increases in TT from PRE (8.37 ± 1.93 ng·ml(-1)) to POST (9.90 ± 1.25 ng·ml(-1)) (p < 0.01) and 15 MIN (9.46 ± 1.27 ng·ml(-1)) (p < 0.05). The S60 elicited significant increases in TT from PRE (7.73 ± 1.88 ng·ml(-1)) to 15 MIN (8.35 ± 1.64 ng·ml(-1)) (p < 0.05), and S90 showed a notable (p < 0.10) difference in TT from PRE (7.96 ± 2.29 ng·ml(-1)) to POST (8.75 ± 2.45 ng·ml(-1)). All the protocols did not significantly increase C (p > 0.05). Using relatively short RI between RT sets augments the acute TT response to hypertrophic and strength schemes. Shortening RI within high-intensity strength RT may lead to concomitant enhancements in muscle strength and size over a longer period of training.

Hormone therapy and maximal eccentric exercise alters myostatin-related gene expression in postmenopausal women.

We sought to evaluate baseline mRNA values and changes in gene expression of myostatin-related factors in postmenopausal women taking hormone therapy (HT) and not taking HT after eccentric exercise. Fourteen postmenopausal women participated including 6 controls not using HT (59 ± 4 years, 63 ± 17 kg) and 8 women using HT (59 ± 4 years, 89 ± 24 kg). The participants performed 10 sets of 10 maximal eccentric repetitions of single-leg extension on a dynamometer. Muscle biopsies from the vastus lateralis were obtained from the exercised leg at baseline and 4 hours after the exercise bout. Gene expression was determined using reverse transcriptase polymerase chain reaction for myostatin, activin receptor IIb (ActRIIb), follistatin, follistatin-related gene (FLRG), follistatin-like-3 (FSTL3), and GDF serum-associated protein-1 (GASP-1). In response to the exercise bout, myostatin and ActRIIb significantly decreased (p < 0.05), and follistatin, FLRG, FSTL3, and GASP-1 significantly increased in both groups (p < 0.05). Significantly greater changes in gene expression of all genes occurred in the HT group than in the control group after the acute eccentric exercise bout (p < 0.05). These data suggest that postmenopausal women using HT express greater myostatin-related gene expression, which may reflect a mechanism by which estrogen influences the preservation of muscle mass. Further, postmenopausal women using HT experienced a profoundly greater myostatin-related response to maximal eccentric exercise.

Rethinking Parkinson Disease: Exploring Gut-Brain Interactions and the Potential Role of Exercise.

Although Parkinson disease (PD) has traditionally been considered a disease of the central nervous system, a bidirectional communication system known as the gut-brain axis can influence PD pathogenesis. The dual-hit hypothesis proposed that PD is due to peripheral dysregulations to the gut microbiota, known as dysbiosis. Since then, further investigation has shown that there are multiple pathological sources associated with PD. However, dysbiosis plays a critical role in the disease process. Substantial evidence has identified that cardinal motor symptoms of PD and disease progression are associated with dysbiosis. In other neurodegenerative disorders, dysbiosis has been linked to cognition. Non-PD research has shown that exercise can effectively restore the gut microbiota. Likewise, exercise has become a well-established strategy to improve cognitive and motor function in PD. However, despite the interaction between the gut and brain, and the exercise benefits on gut health, no research to date has considered the effects of exercise on the gut microbiota in PD. Therefore, the purpose of this Perspective is to explore whether exercise benefits observed in PD could partly be due to restorations to the gut microbiota. First, we will review the gut-brain axis and its influence on motor and cognitive function. Next, we will outline evidence regarding exercise-induced restoration of the gut microbiota in non-PD populations. Finally, we will summarize benefits of exercise on motor-cognitive function in PD, proposing that benefits of exercise seen in PD might actually be due to restorations to the gut microbiota. By positing the gut microbiota as a moderator of exercise improvements to motor and cognitive function, we aim to provide a new perspective for physical therapists to prioritize exercise regimens for individuals with PD that can specifically restore the gut microbiota to better improve PD symptoms and prognosis. IMPACT: This Perspective raises awareness that dysregulations to the gut microbiota have recently been attributed to PD symptoms and pathology and that exercise can be an effective therapeutic strategy to improve gut health in individuals with PD. LAY SUMMARY: People with PD have been found to have reduced microbial diversity in their gut, which can play an important role in the progression of the disease. Physical therapists can design therapeutic exercises that might help improve gut health in people with PD.

Effects of a 12-Week Periodized Resistance Training Program on Resting Brain Activity and Cerebrovascular Function: A Nonrandomized Pilot Trial.

Resistance training is a promising strategy to promote healthy cognitive aging; however, the brain mechanisms by which resistance training benefits cognition have yet to be determined. Here, we examined the effects of a 12-week resistance training program on resting brain activity and cerebrovascular function in 20 healthy older adults (14 females, mean age 69.1 years). In this single group clinical trial, multimodal 3 T magnetic resonance imaging was performed at 3 time points: baseline (preceding a 12-week control period), pre-intervention, and post-intervention. Along with significant improvements in fluid cognition (d = 1.27), 4 significant voxelwise clusters were identified for decreases in resting brain activity after the intervention (Cerebellum, Right Middle Temporal Gyrus, Left Inferior Parietal Lobule, and Right Inferior Parietal Lobule), but none were identified for changes in resting cerebral blood flow. Using a separate region of interest approach, we provide estimates for improved cerebral blood flow, compared with declines over the initial control period, in regions associated with cognitive impairment, such as hippocampal blood flow (d = 0.40), and posterior cingulate blood flow (d = 0.61). Finally, resistance training had a small countermeasure effect on the age-related progression of white matter lesion volume (rank-biserial = -0.22), a biomarker of cerebrovascular disease. These proof-of-concept data support larger trials to determine whether resistance training can attenuate or even reverse salient neurodegenerative processes.

Durability of the effects of testosterone and growth hormone supplementation in older community-dwelling men: the HORMA Trial.

OBJECTIVES: To determine the durability of anabolic effects and adverse events (AEs) after stopping testosterone and growth hormone supplementation in older men. DESIGN: Secondary analysis of a double-masked, randomized controlled trial of testosterone gel (5 or 10 g/daily) plus rhGH (0, 3 or 5 µg/kg/day) with follow-up of outcomes 3 months later. PARTICIPANTS: A total of 108 community-dwelling 65- to 90-year-old men. MEASUREMENTS: Testosterone and IGF-1 levels, body composition (DEXA), 1-repetition maximum (1-RM) strength, stair-climbing power, quality-of-life (QOL) and activity questionnaires, AEs. RESULTS: Despite improvements in body composition during treatment, residual benefits 3 months later (week 28) were variable. For participants with improvements exceeding their week-17 median changes, benefits were sustained at week 28 for lean body mass (1·45 ± 1·63 kg, 45% of week-17 values, P < 0·0001 vs baseline), appendicular skeletal muscle mass (ASMM, 0·71 ± 1·01 kg, 42%, P < 0·0001), total fat (-1·06 ± 2·18 kg, 40%, P < 0·0001) and trunk fat (-0·89 ± 1·42 kg, 50%, P < 0·0001); retention of ASMM was associated with greater week-16 protein intake (P = 0·01). For 1-RM strength, 39%-43% of week-17 improvements (P ≤ 0·05) were retained and associated with better week-17 strength (P < 0·0001), change in testosterone from week 17-to 28 (P = 0·004) and baseline PASE (P = 0·04). Framingham 10-year cardiovascular risks were low (~14%), did not worsen and improved by week 28 (P = 0·0002). The hypothalamic-pituitary-gonadal axis recovered completely. CONCLUSIONS: Durable improvements in muscle mass, strength and fat mass were retained 3 months after discontinuing hormone supplementation in participants with greater than median body composition changes during treatment, but not in others with smaller gains. AEs largely resolved after intervention discontinuation. Additional strategies may be needed to sustain or augment muscle mass and strength gains achieved during short-term hormone therapy.

Conducting a VR Clinical Trial in the Era of COVID-19.

The outbreak of severe acute respiratory syndrome coronavirus 2, also known as Coronavirus Disease 2019 (COVID-19) sparked a global public health pandemic that has impacted every aspect of daily life. Medical research was affected, and many clinical trials were halted to minimize COVID-19 transmission risk and spread while the world navigated this novel virus. Here we describe the relaunch of our virtual reality (VR) pilot clinical trial that uses an in-lab brain and body training program to promote brain health in mid-to-late life older adults, in the era of COVID-19. This case series includes five healthy female participants between 51 and 76 years of age, a subset of a larger VR pilot clinical trial that started pre-pandemic. We developed a revised study protocol based on the Center for Disease Control and World Health Organization guidelines to help manage the spread of COVID-19. Since the limited resumption of clinical trials at our institution in August 2020, we successfully completed over 200 in-lab virtual reality training sessions using our revised protocol. During this time, none of the five participants or three study staff reported any COVID-19 symptoms or reported a positive COVID-19 test. More than 40 voluntary COVID-19 tests were completed by our study staff over the last 6 months. All participants rated our safety protocol as very satisfied or extremely satisfied and that they would be very likely or extremely likely to participate in a VR clinical trial during the pandemic. Based on these findings, we suggest that continued VR clinical trial research during the COVID-19 pandemic is achievable and can be safely resumed if specific safety protocols are in place to mitigate the risk of exposure and spread of COVID-19.

12 weeks of strength training improves fluid cognition in older adults: A nonrandomized pilot trial.

OBJECTIVES: Resistance training (RT) is a promising strategy to slow or prevent fluid cognitive decline during aging. However, the effects of strength-specific RT programs have received little attention. The purpose of this single-group proof of concept clinical trial was to determine whether a 12-week strength training (ST) program could improve fluid cognition in healthy older adults 60 to 80 years of age, and to explore concomitant physiological and psychological changes. METHODS: Twenty participants (69.1 ± 5.8 years, 14 women) completed this study with no drop-outs or severe adverse events. Baseline assessments were completed before an initial 12-week control period, then participants were re-tested at pre-intervention and after the 12-week ST intervention. The NIH Toolbox Cognition Battery and standard physical and psychological measures were administered at all three time points. During the 36 sessions of periodized ST (3 sessions per week), participants were supervised by an exercise specialist and challenged via autoregulatory load progression. RESULTS: Test-retest reliability over the control period was good for fluid cognition and excellent for crystallized cognition. Fluid composite scores significantly increased from pre- to post-intervention (8.2 ± 6.1%, p < 0.01, d = 1.27), while crystallized composite scores did not (-0.5 ± 2.8%, p = 0.46, d = -0.34). Performance on individual fluid instruments, including executive function, attention, working memory, and processing speed, also significantly improved. Surprisingly, changes in fluid composite scores had small negative correlations with changes in muscular strength and sleep quality, but a small positive correlation with changes in muscular power. CONCLUSIONS: Thus, improvements in fluid cognition can be safely achieved in older adults using a 12-week high-intensity ST program, but further controlled studies are needed to confirm these findings. Furthermore, the relationship with other widespread physiological and psychological benefits remains unclear.

Exercise does not influence myostatin and follistatin messenger RNA expression in young women.

We evaluated changes in myostatin, follistatin, and MyoD messenger RNA (mRNA) gene expression using eccentric exercise (EE) and concentric exercise (CE) as probes to better understand the mechanisms of muscle hypertrophy in young women. Twelve women performed single-leg maximal eccentric (n = 6, 25 +/- 1 years, 59 +/- 7 kg) or concentric (n = 6, 24 +/- 1 years, 65 +/- 7 kg) isokinetic knee extension exercise for 7 sessions. Muscle biopsies were taken from the vastus lateralis at baseline, 8 hours after the first exercise session, and 8 hours after the seventh exercise session. In the EE group, there were no changes in myostatin and follistatin (p > or = 0.17); however, MyoD expression increased after 1 exercise bout (p = 0.02). In the CE group, there were no changes in myostatin, follistatin, or MyoD mRNA gene expression (p > or = 0.07). Differences between the EE and CE groups were not significant (p > or = 0.05). These data suggest that a single bout or multiple bouts of maximal EE or CE may not significantly alter myostatin or follistatin mRNA gene expression in young women. However, MyoD mRNA expression seems to increase only after EE.

Potential Indirect Mechanisms of Cognitive Enhancement After Long-Term Resistance Training in Older Adults.

The prevalence of dementia and other age-associated cognitive disorders is steadily increasing worldwide. With no cure after diagnosis, successful treatment likely requires maximum adherence to preventative countermeasures. Many potential risk factors are modifiable through exercise. Specifically, mounting evidence suggests that long-term resistance training (RT) can help maintain cognitive abilities with aging and have additional benefits to overall brain health. Physical therapists are uniquely positioned to administer such clinical interventions designed to slow disease progression. However, a neuroscientific foundation for these benefits must be established to justify the integration of RT for brain health into practice. The mechanisms of cognitive decline are commonly linked to fundamental processes of aging. Even healthy older adults experience decreases in physical capacity, vascular function, brain structure and function, glucose regulation, inflammation, mood, and sleep quality. Yet, clinical trials involving RT in older adults have consistently demonstrated improvements in each of these systems with concomitant enhancement of cognitive performance. Beneficial adaptations may indirectly or directly mediate benefits to brain function, and understanding this relationship can help us develop optimal intervention strategies for the aging population.

Validation of an Automated and Adjustable Blood Pressure System for Use with a Public Health Station.

OBJECTIVE: A new automated and adjustable blood pressure (BP) system has been developed to improve the accuracy of BP measurements on public-use health stations. This self-fitting BP system includes a mechanical cuff that wraps down to the user's arm prior to bladder inflation. The purpose of this study was to validate the adaptable BP system (ABPS) using the current standards from the Association for the Advancement of Medical Instrumentation (AAMI). METHODS: The AAMI/ISO 81060:2013 standards for clinical validation of non-invasive automated arterial BP measurement devices were followed precisely using the same arm sequential method. For each participant, BP was measured over multiple trials by trained observers alternating a reference sphygmomanometer with the ABPS. All study requirements were met with 85 qualifying participants, each with 3 valid paired determinations. RESULTS: The mean difference between ABPS BP and reference BP using all 255 paired determinations was -2.4 ± 7.7 mmHg for systolic and 1.7 ± 5.7 mmHg for diastolic. The standard deviation of the averaged paired determinations per participant was 6.3 mmHg for systolic and 5.2 mmHg for diastolic. Arm circumference measurements had a mean error of -2.1 ± 2.4 cm (R2 = 0.87). A new prediction model for arm circumference was validated using a holdout dataset (R2 = 0.94). CONCLUSION: The results of the study confirm that the ABPS met all benchmarks established by the AAMI. The device accurately measures BP across a wide range of arm circumferences (24-44 cm) and is suitable for use by individuals to self-monitor BP.

Predicting Maximal Oxygen Uptake Using the 3-Minute All-Out Test in High-Intensity Functional Training Athletes.

Maximal oxygen uptake (VO2max) and critical speed (CS) are key fatigue-related measurements that demonstrate a relationship to one another and are indicative of athletic endurance performance. This is especially true for those that participate in competitive fitness events. However, the accessibility to a metabolic analyzer to accurately measure VO2max is expensive and time intensive, whereas CS may be measured in the field using a 3 min all-out test (3MT). Therefore, the purpose of this study was to examine the relationship between VO2max and CS in high-intensity functional training (HIFT) athletes. Twenty-five male and female (age: 27.6 ± 4.5 years; height: 174.5 ± 18.3 cm; weight: 77.4 ± 14.8 kg; body fat: 15.7 ± 6.5%) HIFT athletes performed a 3MT as well as a graded exercise test with 48 h between measurements. True VO2max was determined using a square-wave supramaximal verification phase and CS was measured as the average speed of the last 30 s of the 3MT. A statistically significant and positive correlation was observed between relative VO2max and CS values (r = 0.819, p < 0.001). Based on the significant correlation, a linear regression analysis was completed, including sex, in order to develop a VO2max prediction equation (VO2max (mL/kg/min) = 8.449(CS) + 4.387(F = 0, M = 1) + 14.683; standard error of the estimate = 3.34 mL/kg/min). Observed (47.71 ± 6.54 mL/kg/min) and predicted (47.71 ± 5.7 mL/kg/min) VO2max values were compared using a dependent t-test and no significant difference was displayed between the observed and predicted values (p = 1.000). The typical error, coefficient of variation, and intraclass correlation coefficient were 2.26 mL/kg/min, 4.90%, and 0.864, respectively. The positive and significant relationship between VO2max and CS suggests that the 3MT may be a practical alternative to predicting maximal oxygen uptake when time and access to a metabolic analyzer is limited.

Hormone therapy attenuates exercise-induced skeletal muscle damage in postmenopausal women.

Hormone therapy (HT) is a potential treatment to relieve symptoms of menopause and prevent the onset of disease such as osteoporosis in postmenopausal women. We evaluated changes in markers of exercise-induced skeletal muscle damage and inflammation [serum creatine kinase (CK), serum lactate dehydrogenase (LDH), and skeletal muscle mRNA expression of IL-6, IL-8, IL-15, and TNF-alpha] in postmenopausal women after a high-intensity resistance exercise bout. Fourteen postmenopausal women were divided into two groups: women not using HT (control; n = 6, 59 +/- 4 yr, 63 +/- 17 kg) and women using traditional HT (HT; n = 8, 59 +/- 4 yr, 89 +/- 24 kg). Both groups performed 10 sets of 10 maximal eccentric repetitions of single-leg extension on the Cybex dynamometer at 60 degrees /s with 20-s rest periods between sets. Muscle biopsies of the vastus lateralis were obtained from the exercised leg at baseline and 4 h after the exercise bout. Gene expression was determined by RT-PCR for IL-6, IL-8, IL-15, and TNF-alpha. Blood draws were performed at baseline and 3 days after exercise to measure CK and LDH. Independent t-tests were performed to test group differences (control vs. HT). A probability level of P