Purpose: The optimal load for maximal power output during hang power cleans (HPCs) from a mechanical perspective is the 1-repetition-maximum (1RM) load; however, previous research has reported otherwise. The present study thus aimed to investigate the underlying factors that determine optimal load during HPCs. Methods: Eight competitive Olympic weight lifters performed HPCs at 40%, 60%, 70%, 80%, 90%, 95%, and 100% of their 1RM while the ground-reaction force and bar/body kinematics were simultaneously recorded. The success criterion during HPC was set above parallel squat at the receiving position. Results: Both peak power and relative peak power were maximized at 80% 1RM (3975.7 [439.1] W, 50.4 [6.6] W/kg, respectively). Peak force, force at peak power, and relative values tended to increase with heavier loads (P < .001), while peak system velocity and system velocity at peak power decreased significantly above 80% 1RM (P = .005 and .011, respectively). There were also significant decreases in peak bar velocity (P < .001) and bar displacement (P < .001) toward heavier loads. There was a strong positive correlation between peak bar velocity and bar displacement in 7 of 8 subjects (r > .90, P < .01). The knee joint angle at the receiving position fell below the quarter-squat position above 70% 1RM. Conclusions: Submaximal loads were indeed optimal for maximal power output for HPC when the success criterion was set above the parallel-squat position. However, when the success criterion was defined as the quarter-squat position, the optimal load became the 1RM load.
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Seiichiro Takei, Kuniaki Hirayama and Junichi Okada
Alison Doherty and Graham Cuskelly
Using a multidimensional framework, the authors developed the Community Sport Capacity Scale to measure the key elements of capacity in community sport organizations or clubs and investigate their relative impact on three key indicators of club performance. Presidents or their representatives from 336 community sport organizations in 20 sports across the province of Ontario, Canada, completed the web-based survey measuring the extent of various elements of human resources, infrastructure, finance, planning, and external relationships capacity. The survey also measured club operations, programs, and community presence, identified as key performance outcomes. Controlling for club size, elements representing all five capacity dimensions were significantly associated with the outcomes. The findings highlight the rich information that may be generated from a multidimensional and context-specific perspective on organizational capacity, and indicate implications for building capacity in community sport organizations.
Matthew Katz, Aaron C. Mansfield and B. David Tyler
Sport management researchers have increasingly noted a relationship between sport spectatorship and well-being, with the line of inquiry predicated on transformative sport service research. In this study, the authors contribute to transformative sport service research by utilizing multilevel egocentric network analysis to examine the consumption networks of National Football League fans over the course of one season. The authors utilized a network theory approach to explore how emotional support is created and embedded within sport fans’ networks of interpersonal ties and social relationships. Through multilevel modeling, the authors highlighted how attributes of both the ego (i.e., focal actor) and alter (i.e., individual with whom ego shares a tie) affect emotional support. Previous studies of transformative sport service research and the link between well-being outcomes and sport spectatorship have implicitly examined only ego-level attributes (i.e., team identification), yet the present work suggests that emotional support depends on the interpersonal ties and network structures within which sport fans are embedded.
Margaret Delaney, Meghan Warren, Brian Kinslow, Hendrik de Heer and Kathleen Ganley
Disability is a tremendous public health challenge. No study has assessed whether meeting U.S. Physical Activity guidelines is associated with disability in mobility tasks, activities of daily living, and social participation among U.S. older adults. Using 2011–2016 National Health and Nutrition Examination Survey data, this study examined this relationship among 8,309 individuals aged ≥50 years. Most participants (n = 4,272) did not achieve guidelines, and 2,912 participants were completely inactive. People who did not meet guidelines had higher odds of disability compared with those who did (adjusted odds ratio [AOR] = 1.80) in addition to difficulty with mobility tasks (AOR = 1.85), activities of daily living (AOR = 1.66), and social participation (AOR = 2.09). There was a dose–response effect for each level of activity (inactive, insufficient, and meeting and exceeding recommendations). Among adults aged ≥50 years, meeting the U.S. guidelines was associated with better social and physical functioning.
Nicolas Robin, Lucette Toussaint, Stéphane Sinnapah, Olivier Hue and Guillaume R. Coudevylle
Inactivity is known to have harmful effects on the physical and mental health of older adults. This study used a randomized, parallel trial design to evaluate whether daily text prompts to practice mindfulness would have a positive impact on the time that adults aged 50 years or older spend in aerobic physical activity. The participants were recruited from a certified fitness center and divided into mindfulness and control groups. For 4 weeks, they were exposed to the experimental conditions, with or without the morning text message. In the morning message condition, the mindfulness groups received a text message with the instruction to practice audio-guided mindfulness for 10 min, and the control group received a placebo message. The participants practicing mindfulness reported significantly more weekly minutes of aerobic physical activity and higher intrinsic motivation than the control participants. Mindfulness training was effective at increasing aerobic physical activity duration and might complement physical activity programs.
Andrea R. Taliaferro and Sean M. Bulger
The purpose of this study was to determine expert consensus regarding the essential characteristics of adapted physical education practicum experiences for preservice physical educators. Researchers used a 3-round Delphi procedure involving the repeated circulation of an online questionnaire to a panel of content experts (N = 24). During Round 1, panelists generated 70 items in response to an open-ended prompt. Then, panelists rated these recommendations on importance and feasibility in the following rounds. After the third round, 23 items were eliminated for failing to reach consensus. Of the remaining 47 items, 24 were both very important and feasible (both means >6), 21 were very important (mean ≥ 6) and probably feasible (mean ≥ 5), and 2 were feasible (mean ≥ 6) and moderately important (mean ≥ 5). Four major themes were identified through a post hoc qualitative cluster analysis: program context, teaching and learning activities, outcomes/soft skills, and evaluation of instructor performance.
Stephanie A. Hooker, Laura B. Oswald, Kathryn J. Reid and Kelly G. Baron
Background: Little is known about how daily fluctuations in health behaviors relate to chronic disease risk. The goal of this study was to examine whether variability in physical activity, caloric intake, and sleep is related to body composition (body mass index and body fat percentage). Methods: Healthy adults (N = 103; 64% female) were monitored for 7 days to assess physical activity (SenseWear Armband), caloric intake (daily food diaries), and sleep duration and timing (Actiwatch Spectrum). Data were analyzed using correlations (between- and within-subjects correlations) and regression. Results: The results demonstrated that variabilities in physical activity, caloric intake, and sleep were unrelated. Caloric intake and sleep variability were unrelated to body composition. At greater levels of physical activity variability, any level of physical activity was protective for body composition. Conclusions: These results suggest that among healthy adults, variabilities in health behaviors may be independent of each other, and physical activity variability may be more strongly related to body composition among those who are less active.
Sheng H. Kioh, Sumaiyah Mat, Shahrul B. Kamaruzzaman, Fatimah Ibrahim, Mas S. Mokhtar, Noran N. Hairi, Robert G. Cumming, Phyo K. Myint and Maw P. Tan
The current evidence on the relationship between a higher body mass index (BMI) and falls in older adults is conflicting. This study, therefore, evaluated the relationship between BMI and falls and explored underlying mechanisms for this relationship. Data from 1,340 individuals from the Malaysian Elders Longitudinal Research study, obtained through home-based computer-assisted interviews and followed by hospital-based health checks, were utilized. A history of the presence of falls in the previous 12 months was obtained. The presence of at least one fall in the past 12 months was associated with a higher BMI (odds ratio = 1.03, 95% confidence interval [1.01, 1.06]). The relationship between a higher BMI and falls was, however, attenuated by a lower percentage of lean body mass, which accounted for 69% of the total effect of BMI on the risk of falls. Future studies should now investigate this aforementioned relationship prospectively.
Nathan Philip Hilton, Nicholas Keith Leach, Melissa May Craig, S. Andy Sparks and Lars Robert McNaughton
Enteric-formulated capsules can mitigate gastrointestinal (GI) side effects following sodium bicarbonate (NaHCO3) ingestion; however, it remains unclear how encapsulation alters postingestion symptoms and acid–base balance. The current study aimed to identify the optimal ingestion form to mitigate GI distress following NaHCO3 ingestion. Trained males (n = 14) ingested 300 mg/kg body mass of NaHCO3 in gelatin (GEL), delayed-release (DEL), and enteric-coated (ENT) capsules or a placebo in a randomized cross-over design. Blood bicarbonate anion concentration, potential hydrogen, and GI symptoms were measured pre- and postingestion for 3 hr. Fewer GI symptoms were reported with ENT NaHCO3 than with GEL (p = .012), but not with DEL (p = .106) in the postingestion phase. Symptom severity decreased with DEL (4.6 ± 2.8 arbitrary units) compared with GEL (7.0 ± 2.6 arbitrary units; p = .001) and was lower with ENT (2.8 ± 1.9 arbitrary units) compared with both GEL (p < .0005) and DEL (p = .044) NaHCO3. Blood bicarbonate anion concentration increased in all NaHCO3 conditions compared with the placebo (p < .0005), although this was lower with ENT than with GEL (p = .001) and DEL (p < .0005) NaHCO3. Changes in blood potential hydrogen were reduced with ENT compared with GEL (p = .047) and DEL (p = .047) NaHCO3, with no other differences between the conditions. Ingestion of ENT NaHCO3 attenuates GI disturbances for up to 3 hr postingestion. Therefore, ENT ingestion forms may be favorable for those who report GI disturbances with NaHCO3 supplementation or for those who have previously been deterred from its use altogether.
Hunter S. Waldman, Brandon D. Shepherd, Brendan Egan and Matthew J. McAllister
In the present study, our team aimed to investigate the effects of acute ingestion of a ketone salt (KS) supplement on the cognitive performance in healthy college-aged males during a dual-stress challenge (DSC). Following a peak oxygen uptake test and DSC familiarization, 16 males completed a DSC while cycling at 60% of their respective peak oxygen uptake after ingesting either a commercially available racemic (D- and L-)β-hydroxybutyrate (β-OHB) KS (0.38 g/kg body mass) or a placebo, using a triple-blinded, crossover, and counterbalanced design. The participants consumed the KS or placebo at −60 and −15 min prior to the start of the DSC. Heart rate, rating of perceived exertion, and blood β-OHB and glucose were sampled throughout. The DSC consisted of a mental arithmetic challenge and a modified Stroop Color Word, which alternated every 2 min for 20 min. Upon completion of the DSC, responses for correct, incorrect, and no responses were recorded for the mental arithmetic challenge and Stroop Color Word. Blood β-OHB was elevated with KS by −15 min and remained so throughout (p < .001), peaking at 0.76 ± 0.32 mM. Blood glucose was lower with KS compared with the placebo at −15 and 10 min by 9% and 5%, respectively (both ps < .05). There were no differences between the treatments for heart rate, rating of perceived exertion, mental arithmetic challenge, or Stroop Color Word. Overall, this study suggests that KSs are not effective aids for enhancing cognitive performance during a DSC, which might partially be explained by the inability of currently available commercial KS supplements to elevate β-OHB blood concentrations above ∼1.0 mM.