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Amy Rauer and Lyndsey M. Hornbuckle

The current study explored concordance in spouses’ perceptions about exercise and how these perceptions predicted observed and self-reported marital functioning using a sample of 64 older married couples. Although couples were similarly motivated to exercise, their views on their physical fitness and potential barriers to exercise were uncorrelated. Dyadic analyses suggested that spouses’ exercise perceptions, particularly husbands’, were associated with how spouses treated each other during a marital problem-solving task and with their concurrent and future marital satisfaction. Exploring how spouses’ views of exercise are related to their marital functioning and for whom these links are most salient may highlight potential opportunities and challenges for those wishing to strengthen couples’ individual and relational well-being through exercise.

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Stephen P. Bailey, Julie Hibbard, Darrin La Forge, Madison Mitchell, Bart Roelands, G. Keith Harris and Stephen Folger

Background: Carbohydrate (CHO) mouth rinse (MR) before exercise has been shown to improve physical performance and corticospinal motor excitability. Purpose: To determine the effects of different forms of CHO MR on quadriceps muscle performance and corticospinal motor excitability. Methods: 10 subjects (5 female and 5 male; 25 [1] y, 1.71 [0.03] m, 73 [5] kg) completed 4 conditions (placebo [PLA], 6.4% glucose [GLU], 6.4% maltose [MAL], 6.4% maltodextrin [MDX]). Maximal voluntary contraction (MVIC) of the right quadriceps and motor-evoked potential (MEP) of the right rectus femoris was determined pre (10 min), immediately after, and post (10 min) 20-s MR. MEP was precipitated by transcranial magnetic stimulation during muscle contraction (50% MVIC). Results: The relative change in MEP from pre-measures was different across treatments (P = .025) but was not different across time (P = .357). MEP was greater for all CHO conditions immediately after (GLU = 2.58% [5.33%], MAL = 3.92% [3.90%], MDX = 18.28% [5.57%]) and 10 min after (GLU = 14.09% [13.96%], MAL = 8.64% [8.67%], MDX = 31.54% [12.77%]) MR than PLA (immediately after = −2.19% [4.25%], 10 min = −13.41% [7.46%]). MVC was greater for CHO conditions immediately (GLU = 3.98% [2.49%], MAL = 5.89% [2.29%], MDX = 7.66% [1.93%]) and 10 min after (GLU = 7.22% [2.77%], MAL = 10.26% [4.22%], MDX = 10.18% [1.50%]) MR than PLA (immediately after = −3.24% [1.50%], 10 min = −6.46% [2.22%]). Conclusions: CHO MR increased corticospinal motor excitability and quadriceps muscle after application. The form of CHO used did not influence this response.

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David Morawetz, Tobias Dünnwald, Martin Faulhaber, Hannes Gatterer and Wolfgang Schobersberger

It is well known that acute hypoxia has negative effects on balance performance. An attempt to compensate for the influence of hypoxia on competition performance was made by the application of hyperoxic gases (inspiratory fraction of oxygen > 0.2095) prior to exercise. Purpose: To investigate whether hyperoxic preconditioning (pure-oxygen supplementation prior to exercise) improves balance ability and postural stability during normobaric hypoxia (3500 m) in highly skilled skiers. Methods: In this single-blind randomized, crossover study, 19 subjects performed a 60-s balance test (MFT S3-Check) in a normobaric hypoxic chamber. After a short period of adaptation to hypoxia (60 min), they received either pure oxygen or chamber air for 5 min prior to a balance test (hyperoxic preconditioning vs nonhyperoxic preconditioning). Capillary blood was collected 3 times. Results: Balance performance, indexed by sensory (P = .097), stability (P = .937), and symmetry (P = .202) scores, was not significantly different after the hyperoxic preconditioning phase. Balance performance decreased over time (no group difference). After hyperoxic preconditioning, arterial partial pressure of oxygen increased from 52.7 (4.5) mm Hg to 212.5 (75.8) mm Hg, and oxygen saturation of hemoglobin increased from 85.8% (3.5%) to 98.9% (0.7%) and remained significantly elevated to 90.1% (2.0%) after the balance test. Conclusion: A hyperoxic preconditioning phase does not affect balance performance under hypoxic environmental conditions. A performance-enhancing effect, at least in terms of coordinative functions, was not supported by this study.

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Tiago Turnes, Rogério S.O. Cruz, Fabrizio Caputo and Rafael A. De Aguiar

Purpose: The 2000-m rowing-ergometer test is the most common measure of rowing performance. Because athletes use different intervention strategies for enhancing performance, investigating the effect of preconditioning strategies on the 2000-m test is of great relevance. This study evaluated the effects of different preconditioning strategies on 2000-m rowing-ergometer performance in trained rowers. Methods: A search of electronic databases (PubMed, Google Scholar, and Web of Science) identified 27 effects of different preconditioning strategies from 17 studies. Outcomes were calculated as percentage differences between control and experimental interventions, and data were presented as mean ± 90% confidence interval. Performance data were converted to the same metrics, that is, mean power. Meta-regression analyses were conducted to assess whether performance level or caffeine dose could affect the percentage change. Results: The overall beneficial effect on 2000-m mean power was 2.1% (90% confidence limit [CL] ±0.6%). Training status affected the percentage change with interventions, with a −1.1% (90% CL ±1.2%) possible small decrease for 1.0-W·kg−1 increment in performance baseline. Caffeine consumption most likely improves performance, with superior effect in higher doses (≥6 mg·kg−1). Sodium bicarbonate and beta-alanine consumption resulted in likely (2.6% [90% CL ±1.5%]) and very likely (1.4% [90% CL ±1.2%]) performance improvements, respectively. However, some preconditioning strategies such as heat acclimation, rehydration, and creatine resulted in small to moderate enhancements in 2000-m performance. Conclusions: Supplementation of caffeine and beta-alanine is a popular and effective strategy to improve 2000-m ergometer performance in trained rowers. Additional research is warranted to confirm the benefit of other strategies to 2000-m rowing-ergometer performance.

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João Pedro Nunes, Alex S. Ribeiro, Analiza M. Silva, Brad J. Schoenfeld, Leandro dos Santos, Paolo M. Cunha, Matheus A. Nascimento, Crisieli M. Tomeleri, Hellen C.G. Nabuco, Melissa Antunes, Letícia T. Cyrino and Edilson S. Cyrino

The aim of this study was to analyze the association between muscle quality index (MQI) and phase angle (PhA) after a program of progressive resistance training (RT) in older women. Sixty-six older women with previous RT experience (68.8 ± 4.6 years, 156.6 ± 5.3 cm, 66.0 ± 13.0 kg, and 26.7 ± 4.6 kg/m2) underwent 12 weeks of RT (3 ×/week, eight exercises, and 10–15 repetition maximum). Anthropometry, muscular strength (one-repetition maximum tests), and body composition (dual-energy X-ray absorptiometry and spectral bioimpedance) were measured pre- and posttraining. There were observed significant increases for PhA, MQI, muscular strength, muscle mass, and reactance, whereas no significant changes in body fat and resistance were found. A significant correlation was observed between the RT-induced relative changes in PhA and MQI (r = .620). We conclude that improvements in MQI induced by RT are associated with increases in PhA. Therefore, PhA may be a valid tool to track changes in MQI after 12 weeks of RT in older women.

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Jesudas E. Menon, David J. Stensel, Keith Tolfrey and Stephen F. Burns

Purpose: This study examined how manipulating meal frequency, with and without exercise, affects postprandial triacylglycerol (TAG). Methods: Fourteen sedentary men completed four 2-day trials in a noncounterbalanced random cross-over order: (1) consumption of 1 large high-fat milkshake without exercise (1-CON), (2) consumption of 2 smaller high-fat milkshakes without exercise (2-CON), (3) consumption of 1 large high-fat milkshake with exercise (1-EX), and (4) consumption of 2 small high-fat milkshakes with exercise (2-EX)—total energy intake was standardized across trials. On day 1, participants rested (1-CON and 2-CON) or walked briskly for 60 minutes (1-EX and 2-EX). On day 2, participants consumed either a single large high-fat milkshake (75% fat; 1-CON and 1-EX) for breakfast or 2 smaller isoenergetic milkshakes (2-CON and 2-EX) for breakfast and lunch. Plasma TAG were measured fasting and for 7 hours after breakfast. Results: Peak incremental TAG was 30% lower on 2-EX than 1-CON (P = .04, d = 0.38). Postprandial TAG increased more rapidly in the first 4 hours in 1-CON than other trials; but at 6 hours, TAG was exaggerated in 2-CON compared with 1-CON. Conclusions: Increasing meal frequency after exercise, without altering overall fat intake, attenuates postprandial TAG.

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Colin B. Shore, Gill Hubbard, Trish Gorely, Robert Polson, Angus Hunter and Stuart D. Galloway

Background: Exercise referral schemes (ERS) are prescribed programs to tackle physical inactivity and associated noncommunicable disease. Inconsistencies in reporting, recording, and delivering ERS make it challenging to identify what works, why, and for whom. Methods: Preferred Reporting Items for Systematic Reviews and Meta-Analyses guided this narrative review of reviews. Electronic databases were searched for systematic reviews of ERS. Inclusion criteria and quality assessed through A Measurement Tool to Assess Systematic Reviews (AMSTAR). Data on uptake, attendance, and adherence were extracted. Results: Eleven reviews met inclusion criteria. AMSTAR quality was medium. Uptake ranged between 35% and 81%. Groups more likely to take up ERS included (1) females and (2) older adults. Attendance ranged from 12% to 49%. Men were more likely to attend ERS. Effect of medical diagnosis upon uptake and attendance was inconsistent. Exercises prescribed were unreported; therefore, adherence to exercise prescriptions was unreported. The influence of theoretically informed approaches on uptake, attendance, and adherence was generally lacking; however, self-determination, peer support, and supervision were reported as influencing attendance. Conclusions: There was insufficient reporting across studies about uptake, attendance, and adherence. Complex interventions such as ERS require consistent definitions, recording, and reporting of these key facets, but this is not evident from the existing literature.

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Eric T. Hyde, John D. Omura, Kathleen B. Watson, Janet E. Fulton and Susan A. Carlson

Background: To estimate the proportion of adults’ and parents’ knowledge of the adult aerobic and youth physical activity guidelines, respectively, in the United States. Methods: Data were analyzed from a national sample of adults in the 2017 ConsumerStyles survey. Prevalence of knowledge of the adult aerobic guideline (ie, 150 min/wk of moderate-intensity activity) was estimated among all respondents (n = 3910) and of the youth guideline (ie, 60 min/d of physical activity on 7 d/wk) among parents (n = 1288). Odds ratios were estimated using logistic regression models adjusting for demographic characteristics. Results: Overall, 2.5% (95% confidence interval, 2.0–3.1) of adults and 23.0% (95% confidence interval, 20.5–25.7) of parents were knowledgeable of the adult aerobic and youth guidelines, respectively. After adjustment, odds of knowledge of the adult guideline differed significantly by sex and physical activity level, whereas knowledge of the youth guideline differed by parental education level. Conclusions: Despite the release of the 2008 Physical Activity Guidelines for Americans nearly a decade ago, most US adults and parents lack knowledge of the adult aerobic and youth physical activity guidelines. Effective communication strategies may help raise awareness of current and future editions of national guidelines for physical activity.

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Patricia M. Kelshaw, Trenton E. Gould, Mark Jesunathadas, Nelson Cortes, Amanda Caswell, Elizabeth D. Edwards and Shane V. Caswell

Girls’ lacrosse participation and head injury rates have increased within the past decade. In response, optional headgear was implemented following the recently developed ASTM International lacrosse headgear performance standards. It remains unknown how lacrosse headgear responds to blunt impacts after use. Our purpose was to compare the peak linear acceleration between girls’ lacrosse headgear conditions (pristine and used) during blunt impacts. Pristine headgear (n = 10) were tested in their original condition and used headgear (n = 10) were worn for an entire competitive season. A Cadex Monorail Impactor impacted all headgear following ASTM standards (F1446-15b, F2220-15, and F3137-15) in the required testing locations. A 2 × 7 repeated-measures analysis of variance compared peak linear acceleration among headgear conditions and impact locations with a simple effects analysis planned comparison. There was no difference between headgear conditions for peak linear acceleration (pristine: 47.12 [13.92] g; used: 46.62 [14.84] g; F = 2.11, P > .05). A main effect for impact location (F = 983.52, P < .01), and an interaction effect of condition and impact location (F = 12.79, P < .01) were observed. All headgear, regardless of condition, met the ASTM performance standard. This suggests that headgear performance may not degrade subsequent to a single season of high school girls’ lacrosse.

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Sarah J. Willis, Jules Gellaerts, Benoît Mariani, Patrick Basset, Fabio Borrani and Grégoire P. Millet

Purpose: To examine the net oxygen cost, oxygen kinetics, and kinematics of level and uphill running in elite ultratrail runners. Methods: Twelve top-level ultradistance trail runners performed two 5-min stages of treadmill running (level, 0%, men 15 km·h−1, women 13 km·h−1; uphill, 12%, men 10 km·h−1, women 9 km·h−1). Gas exchanges were measured to obtain the net oxygen cost and assess oxygen kinetics. In addition, running kinematics were recorded with inertial measurement unit motion sensors on the wrist, head, belt, and foot. Results: Relationships resulted between level and uphill running regarding oxygen uptake (V˙O2), respiratory exchange ratio, net energy, and oxygen cost, as well as oxygen kinetics parameters of amplitude and time delay of the primary phase and time to reach V˙O2 steady state. Of interest, net oxygen cost demonstrated a significant correlation between level and uphill conditions (r = .826, P < .01). Kinematics parameters demonstrated relationships between level and uphill running, as well (including contact time, aerial time, stride frequency, and stiffness; all P < .01). Conclusion: This study indicated strong relationships between level and uphill values of net oxygen cost, the time constant of the primary phase of oxygen kinetics, and biomechanical parameters of contact and aerial time, stride frequency, and stiffness in elite mountain ultratrail runners. The results show that these top-level athletes are specially trained for uphill locomotion at the expense of their level running performance and suggest that uphill running is of utmost importance for success in mountain ultratrail races.