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Volume 34 (2024): Issue 4 (Jul 2024)

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Acute and Chronic Weight-Making Practice in Professional Mixed Martial Arts Athletes: An Analysis of 33 Athletes Across 80 Fights

Reid Reale, Junzhu Wang, Charles Hu Stull, Duncan French, Dean Amasinger, and Ran Wang

Mixed martial arts’ popularity has increased in recent years, alongside descriptive research and evidence-based performance recommendations. Guidelines for (both chronic and acute) weight making exist; however, how these translate in real-life scenarios and detailed investigations on practices in larger groups deserve attention. The present study examined the body mass (BM) and composition of 33 professional mixed martial arts athletes preparing for 80 fights. Athletes were supported by on-site dietitians, who encouraged evidence-based practices. Fasted BM was measured throughout the last ∼10 days before all bouts (acute weight management phase). A subset of athletes had body composition assessed before and after the chronic weight loss phase for 40 fights. Most athletes engaged in chronic BM loss, and all engaged in acute weight loss. Many lost fat-free mass (FFM) during the chronic phase, with rates of BM loss <0.5% best preserving FFM. Regardless of losses, the present athletes possessed greater FFM than other combat sport athletes and engaged in greater acute weight loss. Dehydration in the 24–48 hr before the weigh-in was not reflective of weight regain after the weigh-in, rather BM 7–10 days before the weigh-in was most reflective. These findings suggest that many mixed martial arts athletes could increase FFM at the time of competition by maintaining leaner physiques outside of competition and/or allowing increased time to reduce BM chronically. Acutely, athletes can utilize evidence-based protocols, eliminating carbohydrates, fiber, sodium, and finally fluid in a staged approach, before the weigh-in, reducing the amount of sweating required, thus theoretically better protecting health and preserving performance.

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Durability and Underlying Physiological Factors: How Do They Change Throughout a Cycling Season in Semiprofessional Cyclists?

Jens G. Voet, Robert P. Lamberts, Aitor Viribay, Jos J. de Koning, and Teun van Erp

Purpose: To investigate how cycling time-trial (TT) performance changes over a cycling season, both in a “fresh” state and in a “fatigued” state (durability). Additionally, the aim was to explore whether these changes are related to changes in underlying physiological factors such as gross efficiency, energy expenditure (EE), and substrate oxidation (fat oxidation [FatOx] and carbohydrate oxidation [CarbOx]). Methods: Sixteen male semiprofessional cyclists visited the laboratory on 3 occasions during a cycling season (PRE, START, and IN) and underwent a performance test in both fresh and fatigued states (after 38.1 [4.9] kJ/kg), containing a submaximal warm-up for the measurement of gross efficiency, EE, FatOx, and CarbOx and a maximal TT of 1 (TT1min) and 10 minutes (TT10min). Results were compared across states (fresh vs fatigued) and periods (PRE, START, and IN). Results: The average power output (PO) in TT1min decreased (P < .05) from fresh to fatigued state across all observed periods, whereas there was no change in the PO in TT10min. Over the course of the season, the PO in TT1min in the fatigued state improved more compared with the PO in TT1min in the fresh state. Furthermore, while EE did not significantly change, there was an increase in FatOx and a decrease in CarbOx toward the fatigued state. These changes diminished during the cycling season (IN), indicating a greater contribution of CarbOx in the fatigued state. Conclusions: TT1min performance is more sensitive to fatigue compared with TT10min. Also, during a cycling season, durability improves more when compared with fresh maximal POs, which is also observed in the changes in substrate oxidation.

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The Evolution of Physical Activity and Health Research in China: A Bibliometric Analysis of Study Areas and Sex Balance in Authorship

Kaiyue Zhang, Diana Morales, Junshi Chen, Wenhua Zhao, Anne Tang, Eduardo Kohn, Ding Ding, Andrea Ramirez Varela, Michael Pratt, and Pedro C. Hallal

Background: This article evaluates the evolution of physical activity and health research in China through a bibliometric analysis focused on number of publications, study areas, and sex balance in authorship. Methods: A systematic review was conducted by the Global Observatory for Physical Activity for “physical activity and health” publications between 1950 and 2019. Here, we focus on the 610 Chinese publications identified, defined as those in which data collection took place in China. We assessed the number of publications, classified them into 5 areas (1) surveillance, (2) correlates and determinants, (3) health consequences, (4) interventions, and (5) policy, and analyzed female participation in authorship. Results: The first Chinese publication identified in the review was in 1990. Since, the average number of physical activity and health publications increased from one per year in the 1990s to 7.6 per year in the 2000s, and to 47 per year in the 2010s. Most publications focused on the correlates and determinants (38.7%) and the health consequences of physical activity (35.9%). Physical activity policy accounted for 2.3% of the publications. In the 1990s, 64% of the publications included at least one female author; this proportion increased to 90% in the 2010s. Conclusion: Despite a slow start, China’s research on physical activity and health has grown rapidly since 2000. The distribution of publications by study areas and female participation in authorship is similar to that observed globally, with fewer publications focused on interventions and policy as compared with other topics.

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Characterizing Longitudinal Alterations in Postural Control Following Lower Limb Injury in Professional Rugby Union Players

Molly F. McCarthy-Ryan, Stephen D. Mellalieu, Holly Jones, Adam Bruton, and Isabel S. Moore

Assessment of player’s postural control following a lower limb injury is of interest to sports medicine practitioners due to its fundamental role in daily tasks and sporting activities. The aim was to longitudinally monitor professional rugby union players’ postural control during each phase of the rehabilitation program (acute, middle, and late) following a lower limb injury. Seven male rugby union players (height 1.80 [0.02] m; mass 100.3 [11.4] kg; age 24 [4] y) sustained a time loss, noncontact lower limb injury. Static postural control was assessed via sway path (in meters), and dynamic postural control was assessed via vertical postural stability index. Group differences (P < .05) were reported across the acute, middle, and late phase. Smaller magnitudes of sway path were observed for eyes-open sway path, and for the middle and late phase smaller magnitudes of vertical postural stability index (P < .05) at the end session compared with first session. Whereas larger magnitudes of vertical postural stability index were found between baseline and the last session (P < .05). Large interindividual and intraindividual variation was apparent across the 3 phases of rehabilitation. Postural control improvements were identified during rehabilitation. However, postural control did not return to baseline, with altered kinetics throughout each rehabilitation phase.

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Physical Activity Among Utah Cancer Survivors: Analysis From a Population-Based Statewide Survey

Morgan M. Millar, Sandra L. Edwards, Rachel R. Codden, Blessing S. Ofori-Atta, Kimberly A. Herget, Marjorie E. Carter, Anne C. Kirchhoff, Adriana M. Coletta, and Carol Sweeney

Background: Regular physical activity improves cancer survivors’ health-related quality of life and physical function. We estimated the proportion of Utah cancer survivors meeting U.S. Department of Health and Human Services guidelines for weekly physical activity (aerobic plus strength exercise) and identify sociodemographic, cancer, and health-related factors associated with meeting guidelines. Methods: Survivors randomly sampled from Utah Cancer Registry records were surveyed from 2018 to 2022 to ascertain physical activity. We calculated the percent of survivors meeting guidelines and conducted logistic regression to assess predictors of meeting guidelines. Analyses were weighted to account for complex survey sample design and nonresponse and age adjusted. Results: Among Utah cancer survivors, 20.7% (95% CI, 18.5%–23.2%) met guidelines for both aerobic activity and strength exercise. 22.4% reported no aerobic exercise in a typical week, and 59.4% reported no strength exercise. Survivors 75 or older were less likely to meet physical activity guidelines than those under 55 (adjusted odds ratio: 0.40; 95% CI, 0.25–0.65). Survivors with a bachelor’s degree or higher were more likely to meet physical activity guidelines than those without a college degree. Individuals with poorer overall health were less likely to report sufficient physical activity. Individuals treated with both chemotherapy and radiation had decreased odds of meeting guidelines compared to no treatment (adjusted odds ratio: 0.54; 95% CI, 0.29–0.99). Conclusions: Most Utah cancer survivors, and particularly those who received multiple modes of adjuvant treatment, are not participating in sufficient physical activity to improve longevity and quality of life after cancer.

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Reactions From the Experts: Implications of Open-Source ActiGraph Counts for Analyzing Accelerometer Data

Alexander H.K. Montoye, Samuel R. LaMunion, Jan C. Brønd, and Kimberly A. Clevenger

In 2022, it became possible to produce ActiGraph counts from raw accelerometer data without use of ActiLife software. This supports the availability and use of transparent, open-source methods for producing physical behavior outcomes from accelerometer data. However, questions remain regarding the implications of the availability of open-source ActiGraph counts. This Expert Question and Answer paper solicited and summarized feedback from several noted physical behavior measurement experts on five questions related to open-source counts. The experts agreed that open-source, transparent, and translatable methods help with harmonization of accelerometer methods. However, there were mixed views as to the importance of open-source counts and their place in the field moving forward. This Expert Question and Answer provides initial feedback, but more research both within this special issue and to be conducted moving forward will help to inform whether and how open-source counts will be accepted and adopted for use for device-based physical behavior assessments.

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Spaced Use of Social Media Apps Among Motor Practice Trials Impacts Performance Without Influencing Mental Fatigue and Motor Learning

Marina Gonçalves Leal, José Eduardo dos Martírios Luz, Ana Kariele da Silva Santos, Cicero Luciano Alves Costa, Paulo Felipe Ribeiro Bandeira, Cassio de Miranda Meira Jr, and Giordano Marcio Gatinho Bonuzzi

We aimed to investigate the impact of smartphone use during intertrial intervals within a distributed practice regime on mental fatigue, performance, and learning of a balance motor skill. One hundred and thirty-six participants were randomly divided into two groups: the smartphone use group (SMARTPHONE) and the control group (CONTROL). The SMARTPHONE accessed social media during the rest periods within a distributed practice of a balance task, whereas the CONTROL rested passively during the rest periods. The participants practiced the toe-touch task. The participants underwent a pretest consisting of one trial. Subsequently, the participants were engaged in practice, completing six trials interspersed with 2-min intervals of either rest or smartphone use. Following the practice phase, a posttest was conducted, and after 24 hr, we administered a retention test and a transfer test. The number of touches and the number of errors (contacting the ground with the free leg to regain balance) were performance measures. We evaluated the participants’ mental fatigue after the practice session using a visual analog scale. The groups demonstrated similar mental fatigue after practice. Our results suggest that using social media on smartphones during rest periods within a distributed practice impairs performance but not motor learning.

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A Novel Behavioral Intervention to Enhance Physical Activity for Older Veterans in a Skilled Nursing Facility

Julie A. Stutzbach, Kristine S. Hare, Allison M. Gustavson, Danielle L. Derlein, Andrea L. Kellogg, and Jennifer E. Stevens-Lapsley

Physical activity levels during skilled nursing facility (SNF) rehabilitation fall far below what is needed for successful community living and to prevent adverse events. This feasibility study’s purpose was to evaluate the feasibility, acceptability, and preliminary effectiveness of an intervention designed to improve physical activity in patients admitted to SNFs for short-term rehabilitation. High-Intensity Rehabilitation plus Mobility combined a high-intensity (i.e., high weight, low repetition), progressive (increasing in difficulty over time), and functional resistance rehabilitation intervention with a behavioral economics-based physical activity program. The behavioral economics component included five mobility sessions/week with structured goal setting, gamification, and loss aversion (the idea that people are more likely to change a behavior in response to a potential loss over a potential gain). SNF physical therapists, occupational therapists, and a mobility coach implemented the High-Intensity Rehabilitation plus Mobility protocol with older Veterans (n = 18) from a single SNF. Participants demonstrated high adherence to the mobility protocol and were highly satisfied with their rehabilitation. Treatment fidelity scores for clinicians were ≥95%. We did not observe a hypothesized 40% improvement in step counts or time spent upright. However, High-Intensity Rehabilitation plus Mobility participants made clinically important improvements in short physical performance battery scores and gait speed from admission to discharge that were qualitatively similar to or slightly higher than historical cohorts from the same SNF that had received usual care or high-intensity rehabilitation alone. These results suggest a structured physical activity program can be feasibly combined with high-intensity rehabilitation for SNF residents following a hospital stay.

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A Practice Guide for Physical Therapists Prescribing Physical Exercise for Older Adults

Frederico M. Baptista, Rosa Andias, Nelson P. Rocha, and Anabela G. Silva

Introduction: Physical activity and exercise are protective factors for physical and cognitive decline in older adults, but recent studies reveal that a large percentage of this population do not practice exercise at the levels recommended by international guidelines. The frequency, intensity, type, time, volume, and progression (FITT-VP) principles are a widely used method for prescribing physical exercise, allowing the development of a personalized exercise program that meets the needs of each individual. Objectives: This masterclass is intended to serve as a professional application tool for physical therapists who prescribe physical exercise for older adults. We present a section for each FITT-VP principle to facilitate handling these principles individually when prescribing exercise for this population. Methods: Review of the scientific literature and international guidelines on the prescription of physical exercises for older adults. Results: Aerobic, mobility, resistance, balance, and flexibility exercises, as well as functional training, should be included in an exercise program for older adults, which should be progressed using different methods for each of the exercise modalities. Conclusions: An exercise program for older adults should integrate different exercise modalities. Exercise progression should be performed following the FITT-VP principles and some specific progression factors recommended for each exercise modality. Significance: Considering the challenge faced by clinicians in designing a viable exercise program for older adults that responds to international recommendations, with this masterclass we hope to help physical therapists to plan an exercise program that is feasible and at the same time, responds to the expected needs of this population.