Auditing the Representation of Female Athletes in Sports Medicine Research: Achilles Repair.

Background: Establishing evidence-based recommendations specific to female athletes has been overlooked in sports medicine. Achilles tendon rupture is one of the most common musculoskeletal injuries, occurring in 15 to 55 per 100 000 people annually. Differences in injury rates could be due to hormonal effects, as estrogen receptors have been identified in tendons along with decreased tendon strain based on oral contraceptive use. The primary purpose of this study was to audit the representation of female athletes in the literature regarding Achilles repair. Methods: An electronic search was performed using PubMed to identify articles related to Achilles repair using the protocol by Smith et al. Studies were assessed by population, size, athletic caliber, study impact, research theme, and menstrual status. Results: Female representation across all studies was 1783 of 10 673 subjects (16.7%). Composition of included studies was predominantly mixed-sex cohorts with 131 of 169 (77.5%) included studies. Within mixed-sex cohort studies, the total representation of female athletes was 1654 of 8792 participants (18.9%). Thirty-two studies were male only, constituting 1540 participants, whereas 3 studies were female only composed of 86 athletes. Importantly, the disparity between male and female representation worsened as the athletic caliber of the study population increased, with 5.0% female representation in studies with professional athletes. No study collected data related to menstrual status and its potential relationship to Achilles rupture or postoperative outcomes. Conclusion: Mixed-sex cohort studies underrepresented female athletes, and male-only cohort studies were more common than female-only studies. These findings indicate a need for increased representation of female athletes as well as acknowledgment of menstrual status in research related to Achilles repair. Future studies should focus on representation of female athletes and data collection related to sex-specific hormones, hormonal contraceptive use, and menstrual status to improve treatment of Achilles tendon ruptures for female athletes. Level of Evidence: Level IV, case series.

Blood Flow Restriction during Walking Does Not Impact Body Composition or Performance Measures in Highly Trained Runners.

Blood flow restriction (BFR) is a commonly used training modality that has been demonstrated to enhance muscle characteristics such as size and function. The purpose of this study was to determine if a 4-week walking program with or without BFR in healthy, active adults has an effect on body composition, anaerobic, and aerobic running performance. Thirty-three participants, randomized among three groups, completed the walking program, which included five sets of 2 min walking intervals with 1 min rest, with or without BFR, or 10 min walking with BFR. Assessments completed before and after the walking program included body composition, 40-yard sprints, and a VO2MAX test on a treadmill. A two-way ANOVA revealed no changes among the groups nor for any variables at any time (p > 0.05). Additionally, one main effect for time indicated the VO2 at V-slope threshold was greater following training for all groups combined (p = 0.001). The results demonstrate that low volume and intensity walking with BFR for 4 weeks did not provide a sufficient stimulus for changing body composition or performance metrics in a group of very active adults. Longer or more isolated exposure of BFR on the limbs may contribute to more pronounced adaptations.

Motor unit firing rates increase in prepubescent youth following linear periodization resistance exercise training.

PURPOSE: The purpose was to examine the effects of 8-weeks (3 days/week) of linear periodization resistance exercise training (RET) on neuromuscular function in prepubescent youth. METHODS: Twenty-five healthy prepubescent youth (11 males, 14 females, age = 9.1 ± 0.8 years) completed the RET (n = 17) or served as controls (CON, n = 8). Isometric maximal voluntary contractions (MVCs) and trapezoidal submaximal contractions at 35 and 60% MVC of the right leg extensors were performed with surface electromyography (EMG) recorded from the leg extensors [vastus lateralis (VL), rectus femoris, and vastus medialis] and flexors (biceps femoris and semitendinosus). EMG amplitude of the leg extensors and flexors were calculated during the MVCs. Motor unit (MU) action potential trains were decomposed from the surface EMG of the VL for the 35 and 60% MVCs. MU firing rates and action potential amplitudes were regressed against recruitment threshold with the y-intercepts and slopes calculated for each contraction. Total leg extensor muscle cross-sectional area (CSA) was collected using ultrasound images. ANOVA models were used to examine potential differences. RESULTS: Isometric strength increased post-RET (P = 0.006) with no changes in leg extensor and flexor EMG amplitude. Furthermore, there were no changes in total CSA or the MU action potential amplitude vs. recruitment threshold relationships. However, there were increases in the firing rates of the higher-threshold MUs post-RET as indicated with greater y-intercepts (P = 0.003) from the 60% MVC and less negative slope (P = 0.004) of the firing rates vs. recruitment threshold relationships at 35% MVC. CONCLUSIONS: MU adaptations contribute to strength increases following RET in prepubescent youth.

Auditing the Representation of Female Athletes in Sports Medicine Research: Fifth-Metatarsal Fractures.

Background: Female representation within athletics has increased as a result of Title IX, rising popularity, demand for equal compensation, and greater participation in multiple sports. Despite this, gender disparities in sports medicine research are apparent. This project serves to review the literature available on fifth-metatarsal fractures and assess the representation of female athletes in current literature. Methods: We used a standardized protocol to audit the representation of female athletes in sports science and sports medicine research for fifth-metatarsal fractures. Primary factors included population, athletic caliber, menstrual status, research theme, sample of males and females, journal impact factor, and Altmetric score. Results: Thirty articles met the inclusion criteria. A total of 472 fifth-metatarsal fractures were identified, with 373 of 472 fractures (79%) occurring in males and 99 of 472 (21%) in females. The majority of studies (18/30, 60%) were mixed cohort, followed by 10 male only (33.33%), 1 female only (3.33%), and 1 male vs female (3.33%). Out of 831 total patients in the 18 mixed-cohort studies, 605 of 831 patients (72.8%) were male and 226 of 831 patients (27%) were female. All 18 mixed-sex cohorts investigated health outcomes. Male-only studies evaluated health outcomes and performance metrics. No studies investigated female performance. The one female-only study investigated health outcomes and was the only study to account for menstrual status. There was a single metatarsal fracture in this study population. Conclusion: Females are underrepresented in research regarding sports science and sports medicine research for fifth-metatarsal fractures. Research focused on female-only fifth-metatarsal fracture studies exploring the potential impact of female sex-specific factors such as menstrual status in study design are needed.

Psychological Readiness Is Weakly Related to Physical Function Tests at Return to Sport for Men and Not at All for Women Following Anterior Cruciate Ligament Reconstruction and Rehabilitation.

PURPOSE: To assess the relationships between physical function tests of the operative limb and psychological readiness to return to sport (RTS) after anterior cruciate ligament (ACL) reconstruction (return to sport after injury [ACL-RSI]) by sex. A secondary purpose was to quantify sex-specific differences in physical function test outcomes. METHODS: Patient records were retrospectively identified as cases who performed RTS physical function testing (strength, horizontal hops, vertical jumps, single-leg leg press, and drop landing knee excursion, etc.), and completed a 6-question ACL-RSI survey at the time point they were cleared to RTS. Independent t-tests compared all variables between sex at P ≤ .05. Correlations and regression models were produced per sex to identify factors related to operative limb physical function tests and ACL-RSI scores. RESULTS: With a total of 127 patients (63 men; 64 women), there was no difference in ACL-RSI scores and leg press repetitions between sex (P = .32 and P = .12, respectively). There were sex differences for all other physical performance outcomes (P < .001 for all). To estimate readiness using physical function test scores, the men's regression model identified knee excursion (ß = 0.345; P = .033) as the only contributor to ACL-RSI (R2 = 0.089), whereas there was no relationship between physical performance outcomes and ACL-RSI in women (R2 = 0.00, P = 1.00). CONCLUSIONS: Men and women reported similar ACL-RSI scales, indicating high readiness to return to sport. Likely due to sex-related physiological differences, men performed better at most physical function tests. Further, male ACL-RSI could be predicted using only one physical function outcome and 91% variability of the ACL-RSI coming from other contributors not evaluated, as indicated by R2. No physical function variables predict ACL-RSI in women. The evaluated variables are considered the primary indicators relevant for patients to be permitted to RTS yet cannot adequately predict psychological readiness in these patients. LEVEL OF EVIDENCE: Level III, retrospective comparative study.

A Brief Review of the Literature for Published Dual-Energy X-Ray Absorptiometry Protocols for Athletes.

CONTEXT: Dual-energy x-ray absorptiometry (DXA) is widely known for its utility in diagnosing a patient with osteopenia or osteoporosis; however, its utility in evaluation of body composition and potential athletic performance was previously routinely overlooked. In recent years, athletic programs have begun employing this equipment during athlete screening. However, it is currently unknown how athletic programs are utilizing this information to guide an athlete's training and health. OBJECTIVE: To explore the literature to identify what is known regarding sports performance and athlete health based on body composition recordings. DATA SOURCES: PubMed and Google Scholar databases were searched for this brief review. STUDY SELECTION: A focus was placed on articles within the past 10 years that discussed DXA protocols within athletic populations; 14 articles were included in this brief literature review. STUDY DESIGN: Brief literature review. LEVEL OF EVIDENCE: Level 5. DATA EXTRACTION: One member of the research team searched the literature and retrieved articles with the purpose of analyzing and/or explaining DXA imaging in body composition analysis of active persons (primarily athletes). RESULTS: Quality assurance scans with a phantom calibration block as well as athlete prescreening condition and activity standardization was routinely recommended. However, only 1 study reported a specific DXA protocol for athletes, and only 1 study described guidelines for how to report DXA results in athletic populations, suggesting it is plausible yet difficult due to the small changes detectable. CONCLUSION: Due to the limited literature as well as a lack of reference values for specific athletic populations, the authors of this review recommend using the current Nana et al (Int J Sport Nutr Exerc Metab 2015;25:198-215) DXA protocol for performing DXA scans in the athletic population as well as current Hind et al (J Clin Densitom 2018;21:429-443) guidelines for distributing the information.

Effect of six weeks of resistance training on bone preservation in older adults: a randomized control trial.

BACKGROUND: It has been established that chronic resistance exercise contributes to positive changes to bone in older adults. AIMS: This study evaluated the effect of 6 weeks of resistance exercise with either elastic bands or dumbbells vs. a control period on bone morphology of older adults. METHODS: Fifty-seven adults (mean ± SD; age = 66.5 ± 7.09 yrs; height = 165.2 ± 10.6 cm; body mass = 74.5 ± 14.6 kg) were randomized into three groups (dumbbell, elastic, or control). Participants underwent a total body dual-energy X-ray absorptiometry (DXA) scan for total body and segmental bone mineral content (BMC) and bone mineral density (BMD) before and following 6-week intervention. Age-matched Z-scores for BMD and BMC were recorded. Data were analyzed using two-way repeated measures ANOVAs and 0.05 significance level. RESULTS: BMCarm improved for the dumbbell group (p = 0.016) after the training, with no change in BMD for any group (p > 0.05). Additionally, significant (time x treatment group) interaction (p = 0.024) of age-matched Z-scores indicated an improvement in only the dumbbell group after 6 weeks (p = 0.015), with no change in the elastic group despite them having greater Z-scores than the control group. DISCUSSION: This study is the first to demonstrate acute normative adaptations as dumbbell-based programs may promote positive maintenance of bone metrics over 6 weeks, despite the lack of significant change in absolute BMC or BMD. CONCLUSION: Adults did not lose relative bone mass with acute exercise using dumbbells as the external load applied and this may lead to positive changes following chronic training. There was no bone-related impact from elastic bands, suggesting a weighted load or force produced relative to gravity is beneficial.

Various Definitions of Failure Are Used in Studies of Patients Who Underwent Anterior Cruciate Ligament Reconstruction.

Purpose: To conduct a literature review to assess the definitions of anterior cruciate ligament reconstruction (ACLR) failure used throughout the orthopaedic literature. Methods: A systematic search of Embase, Ovid Medline, SPORTDiscus, and Web of Science was conducted by a university librarian to identity level I-IV clinical studies on ACLR failure. Inclusion criteria consisted of patients who underwent ACLR and included a definition of failure of ACLR. Patients who underwent anterior cruciate ligament (ACL) repairs, animal/cadaver studies, review studies, non-English language articles, and non-full text articles were excluded. Failure data were extracted from each study and categorized. Other data that were extracted included follow-up time after ACLR, failure reoperation rate, and failure reoperation procedure. Descriptive statistics was used to analyze the data. Results: Out of 2,775 studies, 104 (3.75%) met inclusion criteria and were analyzed in this review. The most common definition of ACLR failure included the use of a physical examination, specifically Lachman's test (21/104 [20.2%]), anterior laxity assessment, or a Pivot-Shift test (24/104 [35.2%]) or undergoing or requiring revision ACLR (39/104 [37.5%]). Although some studies used quantitative tests or imaging to help define "failure," others simply defined it as graft rerupture that was otherwise not defined (22/104 [22.5%]). Other common definitions included: the use of imaging (magnetic resonance imaging/radiographs) to confirm graft re-rupture (37/104 [35.6%]), patient-reported outcomes (recurrent instability)/patient reported outcomes measures (International Knee Documentation Committee [IKDC], Knee injury and Osteoarthritis Outcome Score [KOOS], Tegner) (18/104 [17.3%]), and the use of an arthrometer (KT-1000/2000, Rollimeter, or Kneelax) (17/104 [16.3%]). The least common definitions included graft failure or rerupture confirmed by arthroscopy (13/104 [12.5%]) and nonrevision surgery (2/104 [1.0%]). The failure rate of this procedure ranged from 0% to 100% depending on the definition of "failure." Conclusion: In this study, we found that a variety of definitions of failure are used among studies published in the orthopaedic literature. The most common criteria for failure of ACLR were the results of physical examination tests (35%), the need for undergoing a revision ACLR (36%), and the use of imaging to diagnose the failure (34%). About 17% of studies included in this review used patient-reported outcomes, specifically recurrent instability, or PROMs (IKDC, KOOS, Tegner) in their assessment of failure of ACLR. The least used definitions of "failure" of ACLR included nonrevision ACLR surgery (2%). Although some studies used similar tests or categories in their definition of failure, there were a variety of score and grade cutoff points between them. Level of Evidence: Level IV, systematic review of Level II-IV studies.

Acute muscle swelling effects of a knee rehabilitation exercise performed with and without blood flow restriction.

This study assessed the acute effect of adding blood flow restriction (BFR) to quad sets on muscle-cross sectional area (mCSA), muscle thickness (MT), echo intensity (EI), and subcutaneous fat-normalized EI (EINORM) of the superficial quadriceps muscles. Twelve males and 12 females (mean±SD; age (yrs): 21.4±2.9; stature (m): 1.76±0.1; body mass (kg): 77.7±2.9) performed 70 repetitions (one set of 30, three sets of 15 repetitions) of bodyweight quad sets separately on each leg, with or without BFR (CON) applied. Rating of perceived exertion was recorded following each set. Panoramic ultrasound images of the vastus lateralis (VL), vastus medialis (VM), and rectus femoris (RF) were captured prior to (PRE), immediately after (IMM-POST), 30- (30-POST), and 60-minutes after (60-POST) after exercise. Sex x condition x time repeated measures ANOVAs assessed differences at p<0.05 for each muscle and dependent variable separately. Although males had larger VM and VL mCSA and VL MT (p<0.05), there were no acute changes from PRE to IMM-POST (p>0.05). There was a 3-way interaction in VL mCSA (p = 0.025) which indicated BFR was greater than CON at IMM-POST by 7.6% (p = 0.019) for males only. Females had greater EI in the VM and VL than males (p<0.05), yet males had greater EINORM for each muscle (p>0.05) and EINORM did not change over time or treatment (p>0.05). The lack of changes in MT, EI, and EINORM indicate that unloaded quad sets do not provide a stimulus to promote fluid shifts or acute changes in muscle size with the exception of IMM-POST in the VL for males. Future research should attempt to elucidate the acute muscular responses of BFR application for lightly loaded rehabilitation exercises in the clinical populations for which they are prescribed.

Evaluation of raw segmental bioelectrical impedance variables throughout anterior cruciate ligament reconstruction rehabilitation.

Background.Raw bioelectrical impedance analysis (BIA) variables are related to physical function in healthy and diseased populations. Therefore, BIA may be an insightful, noninvasive method of assessment to track following anterior cruciate ligament reconstruction (ACLR).Objectives.Evaluate phase angle, reactance and impedance at 50 kHz (PhA50, Xc50, andZ50, respectively) in the operative (OP) and non-operative (NOP) limbs during ACLR rehabilitation.Approach.Seventeen patient (12 M, 5 F; 18.8 ± 4.8 years) clinic reports were evaluated prior to ACLR (PRE), two- (2 W), six- (6 W), and twelve-weeks (12 W) post-ACLR and at return to sport testing (RTS).Setting.All observations occurred during the participant's physical therapy visits.Measurements.A multi-frequency BIA device measured segmental PhA, Xc, andZ. Linear mixed effects models were used to assess any leg and time interaction and changes over leg and time, independently. Any interactions or main effects were considered significant atp< 0.05.Main results.Significant legxtime interactions were observed for each variable. PhA50and Xc50of NOP were higher (p< 0.001) than OP at each time point by an average of by 0.9° and 4.9 Ω, respectively. In OP, PhA50and Xc50decreased from PRE to 2 W and increased from 6 to 12 W and 12 W to RTS (p< 0.01, for all). At RTS, PhA50and Xc50were similar to PRE in OP (p> 0.05). ForZ50, the OP leg did not change over time (p> 0.05).Z50was greater in NOP at 2 and 6 W (p< 0.01, for both). There were differences in PhA50in NOP between PRE and 6 W and from 6 W to RTS (p< 0.05 for both). Xc50did not change (p> 0.05), andZ50PRE was lower than at 2 W (p< 0.05).Significance.A multi-frequency BIA device can detect changes in segmental BIA variables following ACLR.

Epidemiology of Ankle Sprain in the Active-Duty Military Population.

¼: Ankle sprain is one of the most prevalent injuries within the military population, resulting in health-care costs, time away from active duty, and negative impacts on overall readiness. ¼: Female service members appear to be more likely to sustain ankle sprains than male service members. ¼: There is a need for additional research on prevention methods and rehabilitation programs for ankle sprains in the military population because the rate of ankle sprain in this population exceeds that in populations with less physically demanding lifestyles. Consequently, low-cost prevention strategies could yield substantial benefits.

Skeletal muscle analysis of panoramic ultrasound is reliable across multiple raters.

Ultrasound devices are common in muscle physiology laboratories due to their ease of use and validity to assess skeletal muscle characteristics. The current study assessed the reliability of ultrasound skeletal muscle image analysis across multiple raters with limited experience. Vastus lateralis (VL), rectus femoris (RF), and first dorsal interosseus (FDI) images were separately analyzed by three novice raters to determine muscle thickness (MT), cross-sectional area (CSA), and echo-intensity (EI). Separate analyses of variance (ANOVA) assessed statistical differences between and within raters. Intra-class correlation coefficients (ICC) between (inter-rater) and within (intra-rater) raters, the standard error of the measurement (SEM) and minimal difference needed to be considered real were calculated. Inter-rater reliability was high for the VL and RF (ICC: 0.984-0.999), while the FDI was lower (0.614-0.962). Further, intra-rater reliability was greater than 0.961 for each rater. SEM values calculated for inter-rater reliability expressed as a percentage of the mean ranged from 0.4-5.8% across variables. Similarly, SEM values for intra-rater reliability were between 0.8-5.8%, 0.6-3.6%, and 0.4-3.2% for Raters 1, 2 and 3, respectively. Despite this, significant differences (p<0.05) between raters were observed for RF MT and EI, VL CSA and EI, and FDI MT, suggesting that potentially more measurement trials or greater practice time may be necessary to reduce systematic error among multiple raters. Post-image acquisition processing is reliable among and within raters as determined through ICCs and SEMs. This study provided consistent results among three separate novice raters given the same training, a unique yet realistic setting in muscle physiology laboratories.

Treatment of Chronic Ankle Instability in the Military Population: A Systematic Review.

BACKGROUND: The high incidence of ankle sprain within the military sets the stage for prevalent chronic ankle instability. The purpose of this review was to compare and evaluate chronic ankle instability treatment strategies in the military population. METHODS: Electronic databases were systematically searched in accordance with the Preferred Reporting Items for Systematic Reviews guidelines for English-language, human studies with a military patient population that had been diagnosed with and treated for chronic ankle instability. Exclusion criteria were animal, cadaver, and review studies and case reports. RESULTS: Eight studies met the inclusion criteria, representing 695 military service members-625 males (89.9%) and 70 females (10.1%)-and 4 treatment strategies: Broström-related procedures, modified Watson-Jones procedure, Colville's technique, and anatomic lateral ligament reconstruction using semitendinosus tendon allograft. The percentage of satisfactory outcomes was 100% for Colville's technique, and ranged from 73.2% to 94.7% for Broström-related procedures and 72% to 80% for the modified Watson-Jones procedure. Mean American Orthopaedic Foot and Ankle Society scores, anterior drawer displacement, talar tilt, and visual analogue scale scores were also reported. CONCLUSION: This review demonstrates that the Bröstrom procedure has consistently satisfactory outcomes within the military population, and Colville's technique is another promising option for this patient population but would require additional studies to support this claim. LEVELS OF EVIDENCE: Level IV.

Agreement between multifrequency BIA and DXA for assessing segmental appendicular skeletal muscle mass in older adults.

BACKGROUND: Aging presents changes in muscle mass that may lead to sarcopenia. Identifying safe, quick, and accessible methods to assess muscle mass is imperative. AIMS: The purpose of this investigation was to compare the assessments of appendicular skeletal muscle mass (ASMM), fat-free mass (FFM), and fat mass (FM) between bioelectrical impedance analysis (BIA) and dual-energy X-ray absorptiometry (DXA). METHODS: Seventy-three healthy, community-dwelling, physically active males (n = 19) and females (n = 54) (BMI = 27.1 ± 4.3 kg m-2) between the ages of 55-85 years underwent total-body BIA and DXA. ASMM was estimated via BIA from a previously published regression equation while DXA ASMM was calculated as the sum of the measured total arm lean mass and total leg lean mass. Paired-samples t tests with a significance level of p < 0.05 were conducted, while agreement between the methods was assessed via Bland-Altman plots. RESULTS: In comparison to DXA, the chosen BIA equation overestimated ASMM (21.61 ± 5.82 kg vs. 18.82 ± 4.81 kg) and FFM (49.57 ± 9.94 kg vs. 46.22 ± 10.11 kg) and underestimated FM (24.59 ± 8.28 kg vs. 27.13 ± 10.01 kg), all p < 0.001. Visual inspection of the Bland-Altman plots revealed wide limits of agreement. Female participants were more clustered around the mean than male participants. DISCUSSION: The multifrequency BIA device and chosen ASMM estimation equation resulted in wide limits of agreement and significantly different comparisons to the reference method of DXA. CONCLUSION: Future research should continue to investigate and validate methodologies to screen older individuals for characteristics of aging-related diseases, such as sarcopenia.

Evaluation of High-Intensity Interval Training and Beta-Alanine Supplementation on Efficiency of Electrical Activity and Electromyographic Fatigue Threshold.

ABSTRACT: Herda, AA, Smith-Ryan, AE, Kendall, KL, Cramer, JT, and Stout, JR. Evaluation of high-intensity interval training and beta-alanine supplementation on efficiency of electrical activity and electromyographic fatigue threshold. J Strength Cond Res 35(6): 1535-1541, 2021-The purpose of this study was to determine the effects of high-intensity interval training (HIIT) with or without ß-alanine (BA) supplementation on the electromyographic fatigue threshold (EMGFT) and efficiency of electrical activity (EEA) in young women. Forty-four women (mean ± SD; age [yrs]: 21.7 ± 3.7; height [cm]: 166.3 ± 6.4; body mass [kg]: 66.1 ± 10.3) were randomly assigned to one of 3 treatment groups. The supplement groups performed HIIT on the cycle ergometer 3 times·wk-1 for 6 weeks. Electromyographic fatigue threshold and EEA were assessed at baseline (PRE), after 3 weeks of training (MID), and after 6 weeks of HIIT (POST). Two 2-way mixed factorial analyses of variance (time [PRE vs. MID vs. POST] × treatment (BA vs. PL vs. CON)] were used to analyze EMGFT and EEA with a predetermined level of significance α of 0.05. For EMGFT, there was no interaction (p = 0.26) and no main effect for time (p = 0.28) nor treatment (p = 0.86); thus, there were no changes in EMGFT regardless of training or supplementation status. For EEA, there was no interaction (p = 0.70) nor treatment (p = 0.79); however, there was a main effect for time (p < 0.01). Our findings indicated that neither training nor supplementation was effective in improving EMGFT in women. Efficiency of electrical activity was altered, potentially because of a learning effect. Coaches and practitioners may not use these tests to monitor training status; however, they may find EEA as a useful tool to track cycling efficiency.

Short-term resistance training in older adults improves muscle quality: A randomized control trial.

The purpose of this study was to evaluate whether dumbbell resistance training (DBRT) and elastic band resistance training (EBRT) are equally beneficial in the older adult. Sixty-five healthy participants (mean±SD; age=66.5±7.09 years; height=165.2±10.6 cm; body mass=74.5±14.6 kg) volunteered for this study. Participants underwent a total body dual-energy x-ray absorptiometry (DXA) scan for segmental and total body muscle and fat estimation. Functional tests included the short physical performance battery, timed up-and-go, and heel-to-toe walk. Strength was measured on dominant handgrip strength, maximal bench press, and leg press. Participants were block randomized into one of three groups: elastic band resistance training (EBRT), dumbbell resistance training (DBRT), or control (CON). EBRT and DBRT were asked to visit the laboratory twice weekly over 6-weeks while CON maintained their daily routine. Data were analyzed using a two-way repeated measures ANOVA and an alpha set at 0.05. Results indicated there was a two-way interaction for bench press, leg press, upper- and lower-body muscle quality and total arm lean mass (p<0.05). Specifically, the EBRT and DBRT improved from pre to post for total arm lean mass (p<0.021, p<0.004, respectively). Additionally, for bench press and leg press, all groups improved pre to post training (p<0.05) with DBRT superior to CON. These data suggest that EBRT provides an effective, portable, and cost-effective means to enhance lower-body function and muscle quality in an aging population, yet DBRT may be more impactful for total-body improvements.

Changes in Strength, Mobility, and Body Composition Following Self-Selected Exercise in Older Adults.

The purpose of this trial was to examine the effects of self-selected exercise intensities plus either whey protein or placebo supplementation on vital signs, body composition, bone mineral density, muscle strength, and mobility in older adults. A total of 101 participants aged 55 years and older (males [n = 34] and females [n = 67]) were evaluated before and after 12 weeks of self-selected, free-weight resistance exercise plus 30 min of self-paced walking three times per week. The participants were randomized into two groups: whey protein (n = 46) or placebo (n = 55). Three-way mixed factorial analyses of variance were used to test for mean differences for each variable. The 12 weeks of self-selected, self-paced exercise intensities improved resting heart rate, fat-free mass, percent body fat, handgrip strength, bench press strength, leg press strength, and all mobility measurements (p < .05) in males and females despite supplementation status. This suggests that additional protein in well-fed healthy older adults does not enhance the benefit of exercise.

Effects of Short-Term Dynamic Constant External Resistance Training and Subsequent Detraining on Strength of the Trained and Untrained Limbs: A Randomized Trial.

Short-term resistance training has been shown to increase isokinetic muscle strength and performance after only two to nine days of training. The purpose of this study was to examine the effects of three days of unilateral dynamic constant external resistance (DCER) training and detraining on the strength of the trained and untrained legs. Nineteen men were randomly assigned to a DCER training group or a non-training control group. Subjects visited the laboratory eight times, the first visit was a familiarization session, the second visit was a pre-training assessment, the subsequent three visits were for training sessions (if assigned to the training group), and the last three visits were post-training assessments 1, 2, and 3 (i.e., 48 h, 1 week, and 2 weeks after the final training session). Strength increased in both trained and untrained limbs from pre- to post-training assessment 1 for the training group and remained elevated at post-training assessments 2 and 3 (p ≤ 0.05). No changes were observed in the control (p > 0.05). Possible strength gains from short-term resistance training have important implications in clinical rehabilitation settings, sports injury prevention, as well as other allied health fields such as physical therapy, occupational therapy, and athletic training.

Acute effects of passive stretching of the plantarflexor muscles on neuromuscular function: the influence of age.

The acute effects of stretching on peak force (Fpeak), percent voluntary activation (%VA), electromyographic (EMG) amplitude, maximum range of motion (MROM), peak passive torque, the passive resistance to stretch, and the percentage of ROM at EMG onset (%EMGonset) were examined in 18 young and 19 old men. Participants performed a MROM assessment and a maximal voluntary contraction of the plantarflexors before and immediately after 20 min of passive stretching. Fpeak (-11 %), %VA (-6 %), and MG EMG amplitude (-9 %) decreased after stretching in the young, but not the old (P > 0.05). Changes in Fpeak were related to reductions in all muscle activation variables (r = 0.56-0.75), but unrelated to changes in the passive resistance to stretch (P ≥ 0.24). Both groups experienced increases in MROM and peak passive torque and decreases in the passive resistance to stretch. However, the old men experienced greater changes in MROM (P < 0.001) and passive resistance (P = 0.02-0.06). Changes in MROM were correlated to increases in peak passive torque (r = 0.717), and the old men also experienced a nonsignificant greater (P = 0.08) increase in peak passive torque. %EMGonset did not change from pre- to post-stretching for both groups (P = 0.213), but occurred earlier in the old (P = 0.06). The stretching-induced impairments in strength and activation in the young but not the old men may suggest that the neural impairments following stretching are gamma-loop-mediated. In addition, the augmented changes in MROM and passive torque and the lack of change in %EMGonset for the old men may be a result of age-related changes in muscle-tendon behavior.

Photobiomodulation in the treatment of patients with non-center-involving diabetic macular oedema.

PURPOSE: Far-red/near-infrared phototherapy or photobiomodulation (PBM) has recently been reported to be an effective and non-invasive treatment method to inhibit lesions of diabetic retinopathy (DR) in animals. This study investigated the safety and efficacy of PBM in diabetic patients to treat non-center-involving diabetic macular oedema (NCDME). METHODS: This was a non-randomised, consecutive, case series, where 4 patients with type 2 diabetes with NCDME were treated for 160 s per day with PBM for 2-9 months. Demographic data including age, sex, HbA1c%, electronic ETDRS visual acuity, and retinal and macular thickness were measured using spectral domain ocular coherence tomography (SD-OCT) before and after treatment. RESULTS: Four eyes of 4 patients were treated, with fellow eyes serving as untreated controls. Daily PBM treatment for only 80 s per treatment twice daily caused a significant reduction in focal retinal thickening in all 4 treated eyes. No adverse effects attributable to therapy were noted by the patients or study investigators during the study period. CONCLUSIONS: PBM potentially offers a non-invasive and cost-effective therapeutic option for patients with NCDME. Further studies of this therapeutic option in DR are warranted.