The aim of the present study was to compare the frequency of oxygenation determined in the vastus lateralis by near-infrared spectroscopy (NIRS) in light exercise with that at rest. A subject rested in a recumbent position for 5 min and changed body position to a sitting position on a cycle ergometer for 9 min. Then exercise with low intensity (work rate of 60% of maximal oxygen uptake) was carried out for 30 min. Total hemoglobin and myoglobin (THb/Mb) suddenly decreased after the start of exercise and gradually increased until 6 min. Oxygenated hemoglobin and myoglobin (Hb/MbO2) suddenly decreased and returned to a steady state after the start of exercise. The difference between Hb/MbO2 and THb/Mb showed a sudden decrease and then a steady state. This difference was analyzed by fast Fourier transform. The peak frequencies of the power spectrum density (PSD) were 0.0169 + 0.0076 Hz at rest and 0.0117 + 0.0042 Hz in exercise. The peak frequency of PSD was significantly decreased in exercise. In exercise, the range of frequencies was expanded. It is concluded that there are oscillations at rest as well as in exercise and that the frequency of peak PSD becomes lower in exercise than at rest

The purpose of the present study was to examine the effects of muscle glycogen reduction on surface electromyogram (EMG) activity and effort sense and ventilatory responses to intense exercise (IE). Eight subjects performed an IE test in which IE [100-105% of peak O(2) uptake ([Formula: see text]), 2 min] was repeated three times (IE(1st), IE(2nd) and IE(3rd)) at 100-120-min intervals. Each interval consisted of 20-min passive recovery, 40-min submaximal exercise at ventilatory threshold intensity (51.5 ± 2.7% of [Formula: see text]), and a further resting recovery for 40-60 min. Blood pH during IE and subsequent 20-min recovery was significantly higher in the IE(3rd) than in the IE(1st) (P < 0.05). Effort sense of legs during IE was significantly higher in the IE(3rd) than in the IE(1st) and IE(2nd). Integrated EMG (IEMG) measured in the vastus lateralis during IE was significantly lower in the IE(3rd) than in the IE(1st). In contrast, mean power frequency of the EMG was significantly higher in the IE(2nd) and the IE(3rd) than in the IE(1st). Ventilation ([Formula: see text]) in the IE(3rd) was significantly higher than that in the IE(1st) during IE and the first 60 s after the end of IE. These results suggest that ventilatory response to IE is independent of metabolic acidosis and at least partly associated with effort sense elicited by recruitment of type II fibers.

Background. Omentin-1, a novel adipokine expressed in visceral adipose tissue, is negatively correlated with insulin-resistance and obesity. Objective(s). The aim of this study was to investigate the effect of eight weeks of high-intensity interval training on omentin-1 gene expression in visceral adipose tissue and insulin-resistance in male wistar rats. Methods. A total of 26 male Wistar rats (mean weight = 110±10 gr) were purchased from Pasteur Institute in Iran. At first, six rats were separated as base control group and, after eight weeks of feeding with normal diet, were dissected and their visceral adipose tissues were sampled. The remaining rats were given a high-fat diet for eight weeks. After this, seven rats were separated into the non-diabetic fat group (obese HIIT). Then, diabetes was induced on the remaining animals After eight weeks, diabetic rats were divided into two groups-diabetic control group (n=6) and diabetic HIIT exercise group (n=7). The exercise group ran on treadmill for eight weeks-five days a week with a speed of 29-36 m/min and intensity of 90% of VO2 max. The activity was repeated five times in the first week, which increased to 12 times in the last week. A total of 48 hours after last session, fasting blood glucose and insulin were measured. Omentin gene expression was measured from visceral adipose tissue. Results. Results showed that omentin-1 gene expression was increased significantly after eight weeks of HIIT. Blood glucose and insulin-resistance decreased significantly in training groups (p=0.001). Conclusion. It can be concluded that eight weeks of HIIT induce high omentin-1 gene expression and reduce fasting glucose level and insulin-resistance in diabetic male wistar rats.

Objective Consumption of pomegranate extract along with resistance training can improve the blood flow, resting metabolism and cause weight loss. However, their effect on body composition and weight control has not been studied. This study aims to investigate the effect of 8 weeks of resistance training combined with pomegranate extract supplementation on resting metabolic rate, hypertrophy and muscle strength of inactive male college students. Methods In this quasi-experimental study, 42 inactive male college students voluntary participated after signing a written informed consent form. They were randomly divided into four groups: resistance training (n=11), resistance training + supplementation (n=11), supplementation (n=10), and control (n=10). The resistance training was performed for 8 weeks, 3 sessions per week and included two movements for the upper body (barbell chest press and barbell shoulder press) and two movements for the lower body (leg extension and leg press with machine). The pomegranate extract was consumed at a dose of 100 mL 3 times a week (half an hour before training). Data analysis was performed using one-way analysis of variance with least significant difference post hoc test and paired t-test considering a significance level of P≤0.05. Results The rate of muscle hypertrophy (hip circumference) increased significantly after intervention in two groups of resistance training and resistance training + supplementation, which was higher in the combined intervention group (P=0.001). The maximum strength in lower body muscles also increased significantly after intervention in these two groups (P=0.001). Body fat percentage decreased significantly in the resistance training + supplementation group (P=0.03). No significant change was observed in the resting metabolic rate of the study groups (P>0.05). Conclusion It seems that the combination of resistance training with pomegranate extract supplementation increases the muscle strength and hypertrophy in young men.

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