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Effects of cold water immersion and compression garment use after eccentric exercise on recovery
Tatsuhiro Maruyama,Sahiro Mizuno,Kazushige Goto 한국운동영양학회 2019 Physical Activity and Nutrition (Phys Act Nutr) Vol.23 No.1
[Purpose] The combined effect of different types of post-exercise treatment has not been fully explored. We investigated the effect of combined cold water immersion (CWI) and compression garment (CG) use after maximal eccentric exercise on maximal muscle strength, indirect muscle damage markers in the blood, muscle thickness, and muscle soreness score 24 h after exercise. [Methods] Ten men performed two trials (CWI + CG and CON) in random order. In the CWI + CG trial, the subjects performed 15 min of CWI (15°C), followed by wearing of a lower-body CG for 24 h after exercise. In the CON trial, there was no post-exercise treatment. The exercise consisted of 6 × 10 maximal isokinetic (60°·s-1) eccentric knee extensions using one lower limb. The maximal voluntary contraction (MVC) and maximal isokinetic (60°·s-1) strength during knee extension, as well as the indirect muscle damage markers, were evaluated before exercise and 24 h after exercise. [Results] The maximal muscle strength decreased in both trials (p < 0.001), with no difference between them. The exercise-induced elevation in the myoglobin concentration tended to be lower in the CWI + CG trial than in the CON trial (p = 0.060). The difference in the MVC, maximal isokinetic strength, muscle thickness, and muscle soreness score between the trials was not significant. [Conclusion] CWI followed by wearing of a CG after maximal eccentric exercise tended to attenuate the exercise-induced elevation of indirect muscle damage markers in the blood.
Irisin response to downhill running exercise in humans
Yoshifumi Tsuchiya,Sahiro Mizuno,Kazushige Goto 한국운동영양학회 2018 Physical Activity and Nutrition (Phys Act Nutr) Vol.22 No.2
[Purpose] To determine the effects of exercise-induced muscle damage, we examined irisin responses during level running (LR), with less muscle damage, and downhill running (DHR), with greater muscle damage under equivalent exercise duration and oxygen consumption (V3O2) conditions. [Methods] Fifteen healthy men (age: 21.6 ± 2.0 y, height: 170 ± 1.3 cm, weight: 64.8 ± 2.7 kg) were randomly assigned to either the LR group (n = 8) or the DHR group (n = 7). Subjects in the LR group performed treadmill running at 70% of maximum oxygen uptake (V3O2max) for 30 min on a 0% gradient. In contrast, subjects in the DHR group performed the same exercise on a –10% gradient. Blood samples were collected before exercise, immediately after exercise, and 1, 3, and 24 h after exercise. [Results] No significant interaction (group × time) or main effect of group or time was observed for changes in plasma irisin concentrations over time (P > 0.05). However, the area under the curve of plasma irisin concentrations during a 3-h post-exercise period was significantly greater in the DHR (239,197 ± 8,166 ng/mL) group than in the LR (92,293 ± 8,755 ng/ml) group (P < 0.05). The blood lactate, serum cortisol, myoglobin, and plasma interleukin-6 concentrations were significantly higher in the DHR group than in the LR group after exercise (P < 0.05 for all variables). [Conclusion] DHR associated with marked muscle damage promoted a greater increase in exercise-induced irisin did LR after the same duration under identical VO2 conditions.
( Hyejung Hwang ),( Sahiro Mizuno ),( Nobukazu Kasai ),( Chihiro Kojima ),( Daichi Sumi ),( Nanako Hayashi ),( Kazushige Goto ) 한국운동영양학회 2020 Physical Activity and Nutrition (Phys Act Nutr) Vol.24 No.2
[Purpose] The present study investigated the effect of endurance exercise with blood flow restriction (BFR) performed at either 25% maximal oxygen uptake (V3 O2 max) or 40% V3 O2 max) on muscle oxygenation, energy metabolism, and endocrine responses. [Methods] Ten males were recruited in the present study. The subjects performed three trials: (1) endurance exercise at 40% V3 O2 max without BFR (NBFR40), (2) endurance exercise at 25% V3 O2 max with BFR (BFR25), and (3) endurance exercise at 40% V3 O2 max with BFR (BFR40). The exercises were performed for 15 min during which the pedaling frequency was set at 70 rpm. In BFR25 and BFR40, 2 min of pressure phase (equivalent to 160 mmHg) followed by 1 min of release phase were repeated five times (5 × 3 min) throughout 15 minutes of exercise. During exercise, muscle oxygenation and concentration of respiratory gases were measured. The blood samples were collected before exercise, immediately after 15 min of exercise, and at 15, 30, and 60 minutes after completion of exercise. [Results] Deoxygenated hemoglobin (deoxy-Hb) level during exercise was significantly higher with BFR25 and BFR40 than that with NBFR40. BFR40 showed significantly higher total-hemoglobin (total-Hb) than NBFR40 during 2 min of pressure phase. Moreover, exercise-induced lactate elevation and pH reduction were significantly augmented in BFR40, with concomitant increase in serum cortisol concentration after exercise. Carbohydrate (CHO) oxidation was significantly higher with BFR40 than that with NBFR40 and BFR25, whereas fat oxidation was lower with BFR40. [Conclusion] Deoxy-Hb and total Hb levels were significantly increased during 15 min of pedaling exercise in BFR25 and BFR40, indicating augmented local hypoxia and blood volume (blood perfusion) in the muscle. Moreover, low-and moderate-intensity exercise with BFR facilitated CHO oxidation.