This study compared the acute and chronic impact of citrulline malate (CM) supplementation on muscle contractile properties and fatigue rate of the quadriceps. Eighteen recreationally trained males consumed both a placebo (PL) and CM treatment for two separate dosing periods. The first experimental testing session for each dosing period was considered the baseline day, the second session the acute day, and the third session the chronic day, which followed seven consecutive days of supplementation. All testing sessions included exercising on a cycle ergometer at 50%–60% of their max power output for 30 min followed by performing the Thorstensson test on an isokinetic dynamometer. A two-way (Supplement × Time) analysis of variance with repeated measures resulted in no significant interactions (p > .05) (PL: baseline day, acute day, chronic day vs. CM: baseline day, acute day, chronic day) for peak power (in watts) (469 ± 81, 490 ± 97, 502 ± 99 vs. 464 ± 85, 480 ± 103, 501 ± 81); peak torque (in newton meters) (150 ± 26, 157 ± 32, 161 ± 31 vs. 149 ± 27, 156 ± 33, 161 ± 26); fatigue rate (in percentage) (57 ± 9, 57 ± 10, 58 ± 9 vs. 57 ± 10, 56 ± 9, 58 ± 9); and heart rate (in beats per minute) (156 ± 17, 146 ± 13, 146 ± 9 vs. 155 ± 11, 146 ± 11, 146 ± 9). The results of this study suggest that neither acute nor chronic supplementation of CM had an effect on recovery or fatigue rate of the quadriceps.
Alyssa N. Fick, Robert J. Kowalsky, Matthew S. Stone, Christopher M. Hearon, and Tyler M. Farney
Patrick B. Wilson
Urine specific gravity (USG) thresholds are used in practice and research to determine hypohydration. However, some limited research has found that body size and body composition may impact USG, suggesting that fixed cutoffs may be insensitive. Cross-sectional data from 3,634 participants of the 2007–2008 National Health and Nutrition Examination Survey were analyzed. Along with USG, body mass index (BMI), estimated lean body mass (LBM), and dietary intake were quantified. Logistic regression models were used to evaluate whether higher quintiles of BMI and LBM were associated with elevated USG (USG ≥ 1.020 and ≥1.025) after accounting for dietary moisture and sodium. The USG (1.018 ± 0.0003 vs. 1.015 ± 0.0004); BMI (28.4 ± 0.2 vs. 28.0 ± 0.2 kg/m2); LBM (60.9 ± 0.3 vs. 42.2 ± 0.2 kg); dietary moisture (3,401 ± 92 vs. 2,759 ± 49 g/day); and dietary sodium (4,171 ± 85 vs. 2,959 ± 50) were greater in men than in women (p < .05). Men and women in the fifth quintiles of BMI or LBM (vs. Quintile 1) had greater odds (2.00–3.68, p < .05) of elevated USG. (The only exception was for the association between BMI and USG ≥ 1.025 in men.) Being in Quintile 4 of LBM or BMI (vs. Quintile 1) also tended to be associated with higher odds of elevated of USG, though this pattern was more consistent when using USG ≥ 1.020 than USG ≥ 1.025. In summary, BMI and LBM are associated with USG at the population level. These results affirm that USG depends on body size and composition and raise questions about using fixed USG thresholds for determining hypohydration, particularly for people in the upper quintiles of BMI and LBM.
Tue A.H. Lassen, Lars Lindstrøm, Simon Lønbro, and Klavs Madsen
The present study investigated individualized sodium bicarbonate (NaHCO3 −) supplementation in elite orienteers and its effects on alkalosis and performance in a simulated sprint orienteering competition. Twenty-one Danish male and female elite orienteers (age = 25.2 ± 3.6 years, height = 176.4 ± 10.9 cm, body mass = 66.6 ± 7.9 kg) were tested twice in order to identify individual time to peak blood bicarbonate (HCO3 − peak) following supplementation of 0.3 g/kg body mass NaHCO3 with and without warm-up. The athletes also performed two 3.5 km time-trial runs (TT-runs) following individualized timing of NaHCO3 supplementation (SBS) or placebo (PLA) on separate days in a randomized, double-blind, cross-over design. The occurrence of individual peak HCO3 − and pH ranged from 60 to 180 min. Mean HCO3 − and pH in SBS were significantly higher compared with PLA 10 min before and following the TT-run (p < .01). SBS improved overall performance in the 3.5 km TT-run by 6 s compared with PLA (775.5 ± 16.2 s vs. 781.4 ± 16.1 s, respectively; p < .05). SBS improved performance in the last half of the TT-run compared with PLA (p < .01). In conclusion, supplementation with NaHCO3 followed by warm-up resulted in individualized alkalosis peaks ranging from 60 to 180 min. Individualized timing of SBS in elite orienteers induced significant alkalosis before and after a 3.5 km TT and improved overall performance time by 6 s, which occurred in the last half of the time trial. The present data show that the anaerobic buffer system is important for performance in these types of endurance events lasting 12–15 min.
Katie Slattery, Stephen Crowcroft, and Aaron J. Coutts
Minhyun Kim, José A. Santiago, Chan Woong Park, and Emily A. Roper
Grounded in occupational socialization theory, the authors examined adapted physical education (APE) teachers’ job satisfaction. Twelve (nine female and three male) APE teachers who had 3–43 years of teaching experience participated in the study. A semistructured interview was employed. The interviews focused on the participants’ roles and responsibilities. The following questions guided this study: (a) What social agents positively impact APE teachers’ job satisfaction? (b) what APE teachers’ roles and responsibilities are related to job satisfaction? and (c) what type of working conditions are linked to APE teachers’ job satisfaction? Thematic analysis was employed to analyze the data. The following four themes emerged from the analysis: (a) support from administrators, physical education teachers, and colleagues; (b) relevant and meaningful professional development; (c) itinerant working conditions; and (d) seeing students’ progress and achievement. The results of this study provide several implications to enhance APE teachers’ job satisfaction.
Hilkka Kontro, Marta Kozior, Gráinne Whelehan, Miryam Amigo-Benavent, Catherine Norton, Brian P. Carson, and Phil Jakeman
Supplementing postexercise carbohydrate (CHO) intake with protein has been suggested to enhance recovery from endurance exercise. The aim of this study was to investigate whether adding protein to the recovery drink can improve 24-hr recovery when CHO intake is suboptimal. In a double-blind crossover design, 12 trained men performed three 2-day trials consisting of constant-load exercise to reduce glycogen on Day 1, followed by ingestion of a CHO drink (1.2 g·kg−1·2 hr−1) either without or with added whey protein concentrate (CHO + PRO) or whey protein hydrolysate (CHO + PROH) (0.3 g·kg−1·2 hr−1). Arterialized blood glucose and insulin responses were analyzed for 2 hr postingestion. Time-trial performance was measured the next day after another bout of glycogen-reducing exercise. The 30-min time-trial performance did not differ between the three trials (M ± SD, 401 ± 75, 411 ± 80, 404 ± 58 kJ in CHO, CHO + PRO, and CHO + PROH, respectively, p = .83). No significant differences were found in glucose disposal (area under the curve [AUC]) between the postexercise conditions (364 ± 107, 341 ± 76, and 330 ± 147, mmol·L−1·2 hr−1, respectively). Insulin AUC was lower in CHO (18.1 ± 7.7 nmol·L−1·2 hr−1) compared with CHO + PRO and CHO + PROH (24.6 ± 12.4 vs. 24.5 ± 10.6, p = .036 and .015). No difference in insulin AUC was found between CHO + PRO and CHO + PROH. Despite a higher acute insulin response, adding protein to a CHO-based recovery drink after a prolonged, high-intensity exercise bout did not change next-day exercise capacity when overall 24-hr macronutrient and caloric intake was controlled.
Alexandra M. Rodriguez, Alison Ede, Leilani Madrigal, Tiffanye Vargas, and Christy Greenleaf
This study aimed to assess the internalization of sociocultural attitudes and appearance comparison among U.S. athletes with physical disabilities. Female (n = 19) and male (n = 25) athletes between the ages of 18 and 73 years completed a quantitative survey along with two exploratory open-ended questions related to body appearance and influencers. Results showed significant correlations between internalization of the thin and low-body-fat ideal and appearance comparison (r = .55, p < .05) and internalization of the muscular ideal and appearance comparison (r = .76, p < .05) among women. For men, results showed a significant association between internalization of the muscular ideal and appearance comparison (r = .52, p < .05). The findings prompt further investigation of whether appearance comparison and internalization influence body dissatisfaction and disordered eating among athletes with physical disabilities.
Ghada Regaieg, Sonia Sahli, and Gilles Kermarrec
The purpose of this study was to examine the effects of two pedagogical strategies in adapted physical education (hybrid virtual/real vs. conventional) on fundamental movement skills (FMS) in children with intellectual disability age 7–10 years. Children with intellectual disability (N = 24) were randomly assigned to either the hybrid (experimental group) or the conventional (control group) group and were evaluated across 10 weeks. The hybrid program was based on virtual and real game situations, while the conventional program was based on adapted sports. FMS were evaluated using the Test of Gross Motor Development-2 at pre- and postprogram for both groups. Both programs significantly improve locomotor skills, with significantly better improvement in the experimental group. However, a significant improvement was observed only among the experimental group for object-control skills and gross motor quotient. Based on these results, a hybrid program may be considered for FMS improvement.