The purpose of this study was to examine whether the difference between ingestion of nutrition supplements for 8 weeks can regulate physical activities and fatigue recovery. Fifty one middle-aged women participated in this study and were divided into placebo, ingestion of 20g energy supplement and ingestion of 40g energy supplement groups. Energy supplement mainly consists of carbohydrates and proteins. All subjects take in this supplement one time per a day for 8 weeks. Physical activity and fatigue recovery were measured before and after ingestion of energy supplement for 8 weeks by using the Wingate anaerobic and a blood tests. In the Wingate anaerobic test, the peak power(p<.01) and average power(p<.05) were significantly increased in ingestion of 20 and 40g supplement groups compared to the placebo group. Although concentrations of lactate and growth hormone in the blood didn’t show a significant differences among groups, blood concentrations of cortisol and ammonia were further enhanced in ingestion of 20 and 40g supplement groups compared to the placebo group(p<.001). The results of present study provide evidence that energy supplement mixed with carbohydrates and proteins may be effective to increase physical activity as well as to reduce blood concentration of fatigue-related factors after exercise.
PURPOSE The purpose of this study was to identify a sport-specific assessment for elite race walking athletes by comparing physiological responses to different types of walking graded exercise test (GTX) protocols. METHODS Six elite race walking athletes completed two types of walking protocols in a randomized crossover design with 1 week of interval between trials. Exercise time, oxygen uptake (VO2), ventilation (VE), and heart rate (HR) were measured in each trial; the lactate level was measured during the recovery period. RESULTS VO2, VE, and HR differed significantly between the trials (p<.01~.05). Exercise time (p<.01) and VO2 (p<.05) differed significantly between the walking protocols; however, VE and HR did not differ significantly. During the recovery period, lactate levels differed significantly between the trials (p<.01), but not the walking protocol. CONCLUSIONS These results suggest that modified walking GXT protocols were appropriate to assess elite race walking athletes.
[Purpose] The purpose of this study was to examine the effect of recovery methods comparing with change ratio in Lactic acid(LA), Heart rate(HR), VAS(Visual analogue scale) on recovery patterns after field training(FT) in Korea National bobsleigh and skeleton players. [Methods] The tests were conducted for 3 times at a one-week interval as an experimental design within the same subjects(n=9), observed change ratio in LA, HR, VAS through applying Active recovery(AR), Whole body vibration(WBV) & Cold water immersion(CWI) after FT. [Results] The results were summarized as follows: The alteration of ratio in LA, HR, VAS decreased significantly after applying the three recovery patterns(p<.01). The difference between the groups showed that the reduction in lactic acid according to active recovery and whole-body vibration was higher than cold water immersion(p<.01). [Conclusion] In conclusion, although active recovery was more effective than static recovery, there was a significant effect of the three recovery methods in this study on reducing a fatigue in bobsleigh & skeleton players. Therefore, it would be considered to improve the performance of athletes when these methods apply for them depending on situations and environments.
Purpose The purpose of this study was to investigate the effects of coupled high frequency rTMS and prism illusion in elderly stroke patients, based on the result of previous studies which discovered the effect of bilateral training, mirror rehabilitation treatment, and rTMS. Methods This is a case study of 4 stroke patients who were homogeneous on the basis of selection criteria such as brain injury area, duration of onset, degree of upper limb movement function. A total of 24 rehabilitation sessions were conducted three times a week during the training period, and TMS(transcranial magnetic stimulator), EMG, motion analysis system, and prism optical glasses were used for apparatus. Results The results of the study were as follows: Combined rehabilitation exercises were found to be beneficial to restore upper limb function in stroke patients. Particularly, the maximum speed of stretching and JTT(Jebsen-taylor Test) performance showed improvement after training. The amount of total map volume and MEP(megnetic evoked potential) increased in evaluation of neurophysiology. Conclusion The upper limb dysfunction of stroke patients could be restored by combine rehabilitation exercises.
Purpose The purpose of this study was to investigate changes of the cardiovascular system by comparing heart rate (HR) and blood responses to exercise in younger and older adult dogs and to verify the value of dogs as aging model in exercise science research. Methods A total of 11 healthy beagles were divided into 2 groups according to age: younger adult dogs (1~2 years old, 7 animals) and older adult dogs (9~11 years old, 4 animals). Each animal exercised on the treadmill for 25 minutes, twice a week, and for 4 weeks. The exercise intensity was gradually increased by applying four different protocols. Resting HR, HR during exercise, and HR recovery time were determined as HR parameters. Biochemical analysis was performed on blood samples. The independent Student’s t-test and one-way ANOVA were used to analyze the mean difference of each variable. The associations between age and HR parameters were determined using Spearman‘s analysis. Results Older adult dogs showed higher HRs during rest and exercise than younger adult dogs. HR recovery time was significantly longer in older adult dogs than in younger adult dogs. A strong positive relationship was observed between beagles’ age and resting HR, HR during exercise, and HR recovery time, respectively. The heart rate response to the treadmill exercise was similar between the 1st week and 4th week in younger and older adult dogs. Exercise significantly reduced the white blood cell level in older adult dogs and increased the alkali phosphatase level in younger adult dogs. Conclusions The results of this study demonstrated that short-term treadmill exercise may have a positive effect on the aerobic capacity, inflammation, and bone formation, suggesting that dogs are valuable as aging model in exercise science research.
[Purpose] The purpose of this study was to examine the change of muscle damage markers after maximal eccentric exercise and to verify the difference of recovery according to ACTN3 gene polymorphism. [Methods] Fifty healthy males participated in this study. Subjects performed 25 times/1 set (total 2 set) maximal eccentric contractions of the elbow flexor muscles on a modified preacher curl machine with a between-sets rest time of 5 min. Maximal isometric contraction (MIC) was measured 6 times (pre, post, after 24 h, 48 h, 72 h and 96 h). Muscle soreness (SOR) was measured 5 times (pre, after 24 h, 48 h, 72 h and 96 h). Blood samples were collected 5 times (pre, after 24 h, 48 h, 72 h and 96 h). ACTN3 gene polymorphisms were identified using polymerase chain reaction (PCR). Data were analyzed using a 2-way repeated measure ANOVA and post hoc Bonferroni test. [Results] Analysis of ACTN3 gene polymorphism revealed the following distribution: 22% RR (n=11), 50% RX (n=25), and 28% XX (n=14). Individuals were classified into the RR homozygote group (n=11) and the X-allele group (n=39). MIC showed a significant difference between groups and interaction (p<.05). The groups differed significantly in MIC at 48 h, 72 h, and 96 h after exercise and the X-allele group decreased more than the RR homozygote group. The groups differed significantly in muscle soreness and interaction (p<.05). SOR in the X-allele group was significantly higher than in the RR homozygote group at 24 h after exercise. Although blood CK activity was lower in the RR homozygote group than in the X-allele group, but there was no significant difference between the groups (p>.05). [Conclusion] The RR homozygote group showed lower muscle strength reduction rate, muscle soreness and blood CK activity than the X-allele group. This indicates that RR individuals have a lower risk of exercise-induced muscle damage than those with an X-allele.
PURPOSE This study aimed to examine the effect of acute tart cherry juice intake on recovery after intermittent exercise in female field hockey athletes. METHODS Sixteen university female field hockey athletes were studied for a total of 3 days. The cohort was divided into 2 groups, placebo group (n=8, PLA) and the tart cherry juice group (n=8, TCJ), Each supplement was consumed 5 times over 48 hours. On the first day of the study, venous blood was collected before the test, and physical fitness variables (20m sprint, 5-0-5 agility, and Countermovement jump) were performed twice before and after the Yo-Yo Intermediate recovery test 1 to determine the degree of muscle damage and recovery of physical fitness factors. After all tests on Day 1, supplements (PLA, TCJ) were taken. After 24 hours, venous blood collection was performed, and after 48 hours, venous blood collection and physical element variables were measured to verify the effectiveness of tart cherry juice. RESULTS In the TCJ group, a significant effect was found over time in the 5-0-5 ability among the fitness variable items (p<.001) In Countermovement jump (CMJ), there was a significant effect over group and time (p<.001). Second, significant effects over group and time were shown in Interlukin-6 (IL-6) among variable items related to muscle damage and inflammation through venous blood collection (p<.05) and LDH (p<.001), and CK (p<.01) showed a tendency to decrease with time. CONCLUSIONS The results of this study suggest that acute tart cherry juice intake after intermittent exercise tends to reduce muscle damage and inflammation-related variables in female field hockey players, which could help them recover quickly, especially after hectic game schedules.
Although delayed heart rate recovery (HRR) and impaired autonomic nerve system (ANS) modulation after acute exercise are related with cause of cardiovascular disease (CVD) and mortality, studies evaluating ANS changes with local exercise are still unsatisfied. Thus, this study aimed at investigating the modulation of ANS-related parameters, followed by upper or lower body exercise. Eleven male without cardiovascular and orthopedic diseases measured basic body composition, resting blood pressure (BP), and heart rate variability (HRV). This study based on randomized cross-over design; AE composed with arm-ergometer, and LE involved with leg cycling. Participants had at least one week wash-out between each exercise, also there was no cool-down after exercise. All sessions were performed with intensity of 50 % target heart rate for 30 min. With measurement of Rating of perceived exertion (RPE) during every 10 min, HRV was measured Kubios HRV software using R-R intervals collected with Polar RS800CX in post-exercise recovery (for 30 min). As a result, heart rate (HR) and RPE were same (p > 0.05) through the experiment. As results of this study, SDNN and rMSSD in time domain on LE were higher than on AE during post-exercise recovery. When LE compared with AE used by Poincare plot, both parasympathetic reactivation (SD1) and autonomic nerve regulation (SD 2) on LE were higher than AE. Immediately after submaximal exercise, the high-frequency component on LE was significantly greater compared to AE. Also, the LF/HF ratio and LF nu reflecting sympathetic activity were higher on AE than LE. In contrast, the HF/TP ratio and HF nu reflecting vagal tone were greater on LE than AE. In conclusion, this study suggested regional lower body exercise recovers more sufficient than regional upper body exercise after submaximal aerobic exercise at same HR. Local exercise like leg cycling needs a careful approach to apply for accurate exercise prescription and effective training.
PURPOSE Blood pressure (BP) in hypertensive individuals is reduced by the accumulation of post-exercise hypotension (PEH) induced by a long period of training. This study aimed to investigate the effects of intensity of two different aerobic exercises with identical energy expenditure on post-exercise blood pressure and cardiovascular function in prehypertensive men. METHODS Eleven prehypertensive men in their 30s participated in two trials repeatedly. In the first trial, the exercise was moderate in intensity and continuous (MICE) with 70% of VO2max, and the exercise in the second trial was high-intensity interval exercise (HIIE) with 50% and 90% of VO2max. Each exercise was performed for 30 min, and the variables related to BP and cardiovascular function were measured at certain times for 1 hr during the recovery phase. RESULTS Our main findings are as follows: (1) Systolic blood pressure was significantly lower at 30 and 45 min of recovery time than the baseline in the HIIE trial, and systolic blood pressure was significantly lower in the HIIE trial than the MICE trial at 10, 15, and 30 min of recovery time. (2) The rate pressure product was significantly higher in the HIIE trial than the MICE trial at 15, 30, 45, and 60 min of recovery time. (3) The heart rate was significantly higher in the HIIE trial than the MICE trial at 15, 30, 45, and 60 min of recovery time. (4) Stroke volume was significantly lower in the HIIE trial than the MICE trial at 30 min of recovery time. (5) Cardiac output was significantly higher in the HIIE trial than the MICE trial at 15 min of recovery phase. (6) Total vascular conductance was significantly higher in the HIIE trial than the MICE trial at 15 and 30 min of recovery phase. (7) Total peripheral resistance was significantly lower in the HIIE trial than the MICE trial at 15 and 30 min of recovery phase. CONCLUSIONS The HIIE shows a higher cardiovascular stress than MICE; however, HIIE contributes to the augmentation of PEH and improvement of cardiovascular function. Therefore, HIIE rather than MICE should be suggested in BP control and enhancement of cardiovascular function in prehypertensive males.
It has well known that post-exercise hypotension (PEH) after a bout of aerobic exercise was a major mechanism to reduce blood pressure though exercise training, and that citrulline supplementation reduced blood pressure by increasing nitric oxide in vivo. However, the effects of citrulline supplementation on PEH have not been fully elucidated yet. This study was designed to examine the effects of citrulline supplementation on PEH after a bout of aerobic exercise in prehypertensive and normotensive 20s males. The effects of a four-day citrulline or placebo treatment on blood pressure, cardiovascular function, and blood lactate concentration measured at rest and during recovery phase after a bout of exercise performed for 30 min at 70% VO2max were compared and analyzed. All subjects participated in a citrulline trial and a placebo trial repeatedly according to a counter-balanced order. Main results of the present study were as follows: 1) Systolic blood pressure, diastolic blood pressure, and mean arterial pressure measured at 10-60 min of recovery phase in citrulline trial were significantly lower than placebo trial. Rate-pressure product measured at 30 min and 45 min of the recovery phase in citrulline trial was significantly lower than placebo trial. 2) No significant differences were found in heart rate (HR), cardiac output (CO), and total peripheral resistance (TPR) measured during the recovery phase between two trials. There were significant differences in HR, stroke volume, CO, and TPR among times within a trial. 3) No significant difference was found in blood lactate concentration measured at rest and during the recovery phase between two trials. The results would be summarized that the PEH was augmented by the citrulline supplementation, and that burden to cardiac muscle as well as cardiovascular function were not affected by the citrulline supplementation. It was concluded that the short-term citrulline supplementation would be very effective to augment the PEH. A research investigating the effects of citrulline supplementation on the PEH in pre-hypertensive and/or hypertensive individuals would be warranted. In addition, a study examining the effects of citrulline supplementation during long-term exercise training on the blood pressure in hypertensive patients also would be warranted in near future.
