The purpose of this study was to examine whether β-alanine ingestion for 8 weeks can regulate isokinetic knee strength, and 3km record in middle-long distance woman cyclists. Fourteen middle-long woman cyclists participated in this study and were divided into two groups; training group with beta-alanine ingestion and training group with placebo ingestion. All subjects took in beta-alanine or placebo supplement three times per a day for 8 weeks. Physical activity was evaluated by measuring the isokinetic muscular strength and 3km record before and after intervention for 8 weeks. As a results, in isokinetic test, there were significant interrelationships in peak torque of the right and left flexors at 60°/sec, peak torque of the right and left extensors at 180°/sec, peak torque of the right flexors at 180°/sec. In 3km record, result showed a significant interrelationship by groups and time. The results of present study provide evidence that beta-alanine supplement may be effective to increase physical activity and competition record in middle-long woman cyclists.
[Purpose] The purpose of this study was to provide the physiological characteristics of female adults in their 30s by comparing the body composition and the maximal strength of the knee extension and flexion and bilateral ratio and ipsilateral ratio(H/Q: Hamstring and Quadriceps ratio) depending on age. [Methods] Body composition was measured by Hv-ps 7681(GE medical systems Lunar, USA). Isokinetic lower limb muscular strength was measured by Isomed2000(D&R Ferstl GMBH, Germany). 92 volunteers who were chosen by our selection criteria agreed to participate in our study. The participants were divided into three groups depending on age and classified as female adults in twenties(n=30), in thirties(n=34), in forties(n=28). To evaluate differences according to age, One-way ANOVA was used. [Results] The result in the test for female adults is as follows. In body composition, there were significant differences in lean mass, bone mineral density in the legs area among groups(p<.05). In isokinetic test, there were significant differences in muscular strength among groups in extensor of knee(p<.05). [Conclusion] The finding revealed that strength training based on the characteristics depending on age is required and ipsilateral ratio needs to be improved.
PURPOSE The aim of this study was to investigate the effects of 12-week instrumental pilates exercise on isokinetic muscle function and body composition of healthy college women. METHODS Twenty-four college women (aged 21.6±1.3yrs) were recruited to the study. The participants were divided into two groups, as the instrumental pilates group (IPG, n=12) and the control group (CG, n=12). The springboard pilates exercise was conducted 3 times a week for 40~60 minutes during 12 weeks. RESULTS There was significant interaction effects in the right knee and left · right elbow extensor muscles (60°/sec) and left knee flexor and right elbow extensor · flexor muscles (180°/sec)(p<.05, p<.01). There was no significant interaction effects in the muscle mass of the total body, trunk, arms, and legs (NS) and also in the serum growth hormone, insulin-like growth factor-I and 25(OH)Vitamin D (NS). Serum creatine kinase was significantly increased (p<.05). There was also no significant interaction effects in weight, body fat, serum total cholesterol, triglycerides, low & high-density lipoprotein cholesterol (NS). CONCLUSIONS These results suggest that although prolonged instrumental pilates exercise of healthy college women might be improving isokinetic muscle function, there is no increasing effect of muscle mass.
PURPOSE This study aimed to investigate the effects of different resistance training structures on basic physical fitness, 1-repetition maximum (1RM), and isokinetic shoulder and knee muscle functions in male college students. METHODS Forty college students were divided into four groups: control group (CG, n=10), compound set training group (CSG, n=10), pyramid set training group (PSG, n=10), and superset training group (SSG, n=10). Excluding CG, each group performed a different resistance exercise method at an intensity of 60~80% 1RM for 60~90 min, three times a week for eight weeks. To compare the effects of resistance training structures, we confirmed body composition, basic physical fitness, 1RM, as well as isokinetic shoulder and knee functions. RESULTS Results indicated that the PSG exhibited the most significant improvement in relative peak torque in isokinetic shoulder and knee testing compared to the other groups. Additionally, all exercise groups positively affected back strength, 40m sprint, and 1RM compared to the CG, although no significant differences were observed among exercise groups. CONCLUSIONS The findings suggest scientific evidence supporting the effectiveness of pyramidal resistance training in improving isokinetic shoulder and knee muscle functions in male college students.
Purpose The purpose of this manuscript was to investigate the effect of high and low speed blood flow restriction versus non-blood flow restriction isokinetic exercise on isometric muscle strength, muscle fatigue, and muscle contraction displacement. Methods The subjects were consisted of ten males without non-specific muscular skeletal disease. They were classified into four training groups: ① high speed(300°/s) without blood flow restriction, ② high speed(300°/s) under blood flow restriction, ③ low speed(90°/s) without blood flow restriction, ④ low speed(90°/s) under blood flow restriction. Before and after the intervention, all of the subjects underwent measurements of isometric quadriceps strength, muscle fatigue, and muscle contraction displacement. Results In regard to isometric quadriceps strength before & after intervention, there was no significant difference between groups. For the lactic acid measurement before & after intervention, there was a signigicant difference between groups(p<.05). Also, there was a significant difference between groups(p<.05) in muscle contraction displacement in terms of Dm but there was no significant difference between groups in terms of Tc Conclusions Isokinetic exercise with blood flow restriction had effects on lactic acid and muscle contraction displacement.
Purpose This study was conducted to analyze the differences of physical characteristics focused on the physique, strength, and power for cycling national athletes (Sprint cyclists and Road race cyclists). Methods We measured various factors (e.g., height, weight, body fat ratio, thigh circumference, waist circumference, anaerobic power, isokinetic muscular strength, muscle power, squat jump by 1RM intensity, and so on) for a total 11 male cycling national athletes (5 Sprint cyclists and 6 Road race cyclists). Results First, the body composition showed the significant differences only in weight (p=0.31) and BMI (p=.001) for Sprint cyclists. Second, the values of the anaerobic power for the Sprint cyclists were significantly higher than those for the Road race cyclists only at peak power (p=0.28), whereas there was no significant difference in average power, isokinetic muscular strength, and muscle power between the two groups. Third, the isokinetic trunk flexion muscle (p = .016) for the Sprint cyclists were significantly higher than those for the Road race cyclists. Fourth, the significant difference in Time to Peak Torque was not found between two groups. Fifth, the values for the Sprint cyclists showed the significant difference in all 5 intensity groups (0%, 30%, 50%, 60%, and 80%) (p=.001) of the squat jump. Also, there was a statistically significant difference only in 0% velocity between the two groups, except for exercise intensity. Conclusions From the various measures between two groups, the Sprint cyclists relatively showed the high weight, BMI (muscle mass), and maximum power. Additionally, the isokinetic trunk flexion muscle and the squat jump were higher in the Sprint cyclists than the Road race cyclists. These data may be used as basic data to improve the physical fitness factors related to the athletic performance of the athletes by reflecting them in the effective training plan and evaluation of the athletes.
Purpose The purpose of this study was to identify the effect of a power-specific weight training program in order to improve the muscle strength of Korean national team’s freestyle wrestlers. Methods Participants were 13 male athletes in the national freestyle wrestling team. The period of the program was 6 weeks. Muscle strength, muscular endurance, muscle power, flexibility, agility, cardiorespiratory endurance, anaerobic power and isokinetic muscle function were measured. Data were analyzed using IBM SPSS Statistics ver. 23.0 (IBM Co., Armonk, NY, USA). Paired t-test was conducted for comparison between pre-test and post-test score. Results There were significant difference and tendency in the leg isokinetic power and trunk isokinetic flexion strength. However, there was no significant difference in muscle strength, muscular endurance, muscle power, flexibility, agility and cardiorespiratory endurance. Conclusion The 6-week program focusing on the power-specific weight training indicated a significant difference not in every variable but in isokinetic muscle power, speed power and core strength. It is suggested that the training program was applied to the athletes less continuously and not in the long term because of frequent international games abroad and the need for losing weight. Consequently, a year-long training program with personalized methods should be developed to bring about more significant outcomes.
The purpose of this study is to investigate the influence of resistance training with different exercise intensities on heart rate variability(HRV) in habitual smokers. Twenty-eight healthy young smokers participated in this study were randomly divided into three groups; CON(control), LRT(low-intensity resistance training; 50% 1RM), and HRT(high-intensity resistance training; 70%1RM), respectively. LRT and HRT groups performed an 8-week resistance training(4 upper- and lower body exercises) using weight training machines, whereas CON group maintained their regular activities. All groups were evaluated basal body composition, hemodynamic parameters, HRV as autonomic nervous function, and muscular strength (1RM and isokinetic test) before and after the 8-week training. To assess the effect of 8-week training with different intensities on autonomic regulation, time and frequency domain indices of HRV were calculated from 5min R-R interval recording. As results, both LRT and HRT groups increased baseline 1RM and isokinetic strength compared to CON group. Meanwhile, high-frequency power reflecting parasympathetic activity was significantly increased in HRT compared to CON group. In addition, normalized low frequency power(LF nu) indicating a shift of sympathovagal balance towards sympathetic predominance significantly decreased while normalized high frequency power(HF nu) which reflects vagal predominance significantly increased in HRT compared to CON group. Furthermore, improved cardiac autonomic regulation and parasympathetic activation had significant association with increased muscular strength. Overall, the 8-week training has enhanced muscular strength in both training groups, particularly autonomic balance improved in young habitual smokers with high intensity resistance training.
