Effects of Cooling and Magnesium on the Regulation of Physiological Mechanisms After Acute Physical Exercise

• Main Authors: LI SHUTING, 黎淑婷
• Other Authors: JANG, Jia-Tzer
• Format: Others
• Language: en_US
• Published: 2019
• Online Access: http://ndltd.ncl.edu.tw/handle/4bczs5

碩士 === 國立體育大學 === 國際運動教練科學碩士學位學程 === 107 === Background: It is known that body temperature and imbalanced ion conditions can limit physical performance. To date, no investigations have evaluated the beneficial effects of varying cryotherapy interventions modalities and the acute magnesium iron supplementation in enhancing physical performance. We hypothesized that cryotherapy and magnesium supplementation will increase the physical performance and mental attitude of athletes. Methods: Twenty-four recreational athletes (doing regular exercises) were recruited (n=24, all male): age 25±4 years, weight 76±10 kg, height 175±5 cm, were respectively. The experiment consisted of two parts: pre-test part, and experimental parts. In pre-test part, all subjects did 400 m rowing as homogeneity analysis divided into four groups (6 subjects/group), each group participated only one intervention. In the experimental part, there were four different interventions (① control group ② hand cooling ③ whole body cooling and ④ magnesium supplementation). Each intervention had three sections, which before exercise interventions, acute high intensity 1000 m open-end rowing (until exhaustion) and recovery intervention period. During rowing, mean watt, speed, were collected in every 200 m. Before and after rowing the following blood plasma parameters were collected: NH3, lactate, heart rate (HR), tympanic temperature (Tear), whole-body temperature (Tw), and rate of perceived exertion (RPE by standard questionnaire) were also collected. At the end of exercise, subjects were asked to rate their perception of thermal sensation (TS) on a scale of 1 (cold) to 7 (hot) in 1 increments. All subjects were independent sample. Results: The measured physiological parameters (lactate, NH3, mean watt and rowing speed were not significantly different (p＞ 0.05) between interventions, but the whole body temperature (Tw) decreased (p＜.00, 29.7±0.70), thermal sensation (TS) decreased and the rate of perceived exertion (RPE) decreased significantly (p＜.05). Conclusions: Based on the results we suggest that cooling and magnesium supplementation - although did not improved the physiological parameters - but significantly decreased the body temperature and thermal sensation and perceived difficulty of exercise, which could be important in the prevention of drop out cases in sport and continue the training program.