Cold water immersion of the hand and forearm during half-time improves intermittent exercise performance in the heat

The present study aimed to investigate the effect of cold water immersion of the hand and forearm during half-time (HT) on intermittent exercise performance and thermoregulation by imitating intermittent athletic games in the heat. In a randomized crossover design, 11 physically active men performed the first half (first and second block) and second half (third and fourth block) intermittent cycling exercise protocol, which consisted of a 5-s maximal power pedalling (body weight × 0.075 kp) every minute separated by 25-s of unloaded pedalling and rest (30 s) in the heat (33°C, 50% relative humidity). The two-halves were separated by a 15-min HT. During HT, the participants were assigned to the CON (sedentary resting) or COOL (immersion of hands and forearms in cold water at 15–17°C) condition. The mean power output in the second half was significantly greater (third and fourth block: p < 0.05) in the COOL than in the CON condition. Moreover, there was a significant decrease in the rectal (0.54 ± 0.17°C, p < 0.001) and mean skin (1.86 ± 0.34°C, p < 0.05) temperatures of the COOL condition during HT. Furthermore, the heart rate (16 ± 7 bpm, p < 0.05) and skin blood flow (40.2 ± 10.5%, p < 0.001) decreased at the end of HT in the COOL condition. In the second half, thermal sensation was more comfortable in the COOL condition (p < 0.001). Cold water immersion of the hand and forearm during HT improved physiological and reduced perceived heat stress. Moreover, it prevented a reduction in intermittent exercise performance in the second half

Different patterns of walking and postprandial triglycerides in older women

Purpose: Although a single bout of continuous exercise (≥30 min) reduces postprandial triglyceride (TG), little evidence is available regarding the effect of multiple short (≤10 min) bouts of exercise on postprandial TG in individuals at increased risk of cardiovascular diseases. This study compared the effect of different patterns of walking on postprandial TG in postmenopausal, older women with hypertriglyceridemia. Methods: Twelve inactive women (aged 71 ± 5 yrs, mean ± S.D.) with hypertriglyceridemia (fasting TG ≥ 1.70 mmol/L) completed three, one-day laboratory-based trials in a random order: 1) control, 2) continuous walking, and 3) multiple short bouts of walking. On the control trial, participants sat in a chair for 8 hours. For the walking trials, participants walked briskly in either one 30-min bout in the morning (0900-0930) or twenty 90-sec bouts over 8 hours. Except for walking both exercise trials mimicked the control trial. In each trial, participants consumed a standardized breakfast (0800) and lunch (1100). Venous blood samples were collected in the fasted state and at 2, 4, 6 and 8 h after breakfast. Results: The serum TG incremental area under the curve was 35% and 33% lower on the continuous and multiple short bouts of walking trials than the control trial (8.2 ± 3.1 vs 8.5 ± 5.4 vs 12.7 ± 5.8 mmol∙8h/L respectively, main effect of trial: ES = 0.459, P = 0.001). Conclusions: Accumulating walking in short bouts limits postprandial TG in at-risk, inactive older women with fasting hypertriglyceridemia

保健体育科教育実習における実習生の「生徒理解」の実態に関する事例研究 : 「フォーカス・スチューデント」を対象として

The purpose of this study was to clarify how trainees perceived “student understanding” based learning, in teaching practices within the health and physical education department. A case study was conducted to examine the actual situation of reflection in trainees, who were selected as focus students. Addressing the quality of social relationships, the results showed the need for improved quality relationships between students and teaching materials, from the perspective of "student understanding" through t he teacher student relationship. In addition, the results showed that a teachers’ responsible behavior was perceived as "student understanding," that originated from a receptive attitude. Furthermore, from the viewpoint of self understanding, the results showed that emotional experience as readiness is a factor. The aforementioned information can help infer that, learning through “student understanding” has influenced the emotional aspects of becoming a teacher

High-intensity cycling re-warm up within a very short time-frame increases the subsequent intermittent sprint performance

This study investigated the effect of high-intensity cycling re-warm up (RW) within a very short time-frame on the subsequent intermittent sprint performance. Twelve active males completed three trials in random order: control (CON); 3-min RW at 30% of maximal oxygen uptake (VO2max) (RW30); and 1-min RW at 90% of VO2max (RW90). During the experimental trials, participants performed 40-min intermittent cycling exercise followed by 15-min rest. During the rest period, participants completed CON, RW30, or RW90. After the rest period, participants performed the Cycling Intermittent-Sprint Protocol (CISP), which consisted of 10-s rest, 5-s maximal sprint, and 105-s active recovery with the cycles repeated over 10 min. The mean work during sprint for the CISP was significantly higher in both RW trials than in the CON trial (mean±standard deviation; CON: 3539±698 J; RW30: 3724±720 J; RW90: 3739±736 J; p<0.05). The mean electromyogram amplitude during the sprint for the CISP was higher in the RW30 trial than in the CON trial; however, there was no significant difference between the two trials (p=0.06). The mean median frequency during sprint for the CISP was significantly higher in the RW90 trial than in the other trials (p<0.05). Rectal temperature did not differ among the three trials. Oxygenated haemoglobin during the initial 30 s of the CISP was significantly higher in the RW90 trial than in the CON trial (p<0.05). Compared with seated rest, RW, irrespective of whether it comprised 1-min at 90% of VO2max or 3-min at 30% of VO2max, increased the subsequent intermittent sprint performance.This study was supported by JSPS KAKENHI Grant Number 17J02878 (to TY) and internal funding from the Waseda University (to MM and NH)

The Effect of Half-time Re-Warm up Duration on Intermittent Sprint Performance

The purpose of the present study was to investigate the effect of different durations of half-time re-warm up (RW) on intermittent sprint performance. Using a randomized crossover design, 13 healthy men performed three trials, which consisted of two, 40-min intermittent exercises separated by a 15-min half-time. Half-time interventions were 15 min of seated rest (Control), 7 min of cycling at 70% of maximal heart rate (HRmax) (7 min RW), and 3 min of cycling at 70% of HRmax (3 min RW). The second 40-min intermittent exercise as an exercise performance test was the Cycling Intermittent-Sprint Protocol (CISP), which consisted of 10 s of rest, 5 s of maximal sprint, and 105 s of low-intensity exercise at 50% of VO2max, with the cycles repeated over the 40-min duration. The mean work during the maximal sprint in the initial 10 min of the CISP was higher in the both RW trials than in the control trial (control: 3638 ± 906 J, 7 min RW: 3808 ± 949 J, p < 0.05, 3 min RW: 3827 ± 960 J, p < 0.05). There were no significant differences among three trials for mean work at 10-20, 20-30, and 30-40 min of the CISP. In the initial 10 min of the CISP, the change in oxygenated hemoglobin concentration during the 105 s of exercise at 50% of VO2max, oxygen uptake, carbon dioxide production, and respiratory exchange ratio were higher in both RW trials than in the control trial (p < 0.05). The rating of perceived exertion after half-time interventions was higher in both RW trials than in the control trial (p < 0.05). In conclusion, the 3 min RW increased intermittent sprint performance after the half-time, compared with a traditional passive half-time practice, and was as effective in improving intermittent sprint performance as the 7 min RW

Different Patterns of Walking and Postprandial Triglycerides in Older Women

This is an Open Access Article. It is published by Lippincott, Williams & Wilkins under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International (CC BY-NC-ND). Full details of this licence are available at: http://creativecommons.org/licenses/by-nc-nd/4.0/Purpose: Although a single bout of continuous exercise (≥30 min) reduces postprandial triglyceride (TG), little evidence is available regarding the effect of multiple short (≤10 min) bouts of exercise on postprandial TG in individuals at increased risk of cardiovascular diseases. This study compared the effect of different patterns of walking on postprandial TG in postmenopausal, older women with hypertriglyceridemia. Methods: Twelve inactive women (aged 71 ± 5 yrs, mean ± S.D.) with hypertriglyceridemia (fasting TG ≥ 1.70 mmol/L) completed three, one-day laboratory-based trials in a random order: 1) control, 2) continuous walking, and 3) multiple short bouts of walking. On the control trial, participants sat in a chair for 8 hours. For the walking trials, participants walked briskly in either one 30-min bout in the morning (0900-0930) or twenty 90-sec bouts over 8 hours. Except for walking both exercise trials mimicked the control trial. In each trial, participants consumed a standardized breakfast (0800) and lunch (1100). Venous blood samples were collected in the fasted state and at 2, 4, 6 and 8 h after breakfast. Results: The serum TG incremental area under the curve was 35% and 33% lower on the continuous and multiple short bouts of walking trials than the control trial (8.2 ± 3.1 vs 8.5 ± 5.4 vs 12.7 ± 5.8 mmol∙8h/L respectively, main effect of trial: ES = 0.459, P = 0.001). Conclusions: Accumulating walking in short bouts limits postprandial TG in at-risk, inactive older women with fasting hypertriglyceridemia