One-hour after-school exercise ameliorates central adiposity and lipids in overweight Chinese adolescents: a randomized controlled trial / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>The prevalence of overweight and obesity in Chinese children and adolescents was increasing during the past few decades. The goal of this study was to investigate the effects of after-school exercise with or without diet restriction on total and central obesity, fitness level, and metabolic profile in overweight Chinese adolescents.</p><p><b>METHODS</b>A ten-week weight loss trial was performed using a 2 × 2 block design (exercise × diet). Ninety-three overweight adolescents (average age: (13.6 ± 0.7) years; body mass index (BMI): 22.4 - 34.1 kg/m(2)) were randomly assigned to four groups: 1) diet (D); 2) exercise (EX); 3) diet plus exercise (DEX); and 4) overweight control (C). Caloric intake recipes were enacted based on individual age and corresponding ideal body weight. One-hour after-school exercise was performed once per day, four days per week for ten weeks. Changes of anthropometry, body composition, aerobic fitness, and metabolic biomarkers were determined.</p><p><b>RESULTS</b>Groups D, EX and DEX had a significant decrease in BMI (P < 0.01) after the intervention. The percentage of body and truncal fat, and waist circumference were independently reduced by exercise (P < 0.05 and P < 0.01), but not diet. The decrease in body fat percentage was positively related with the exercise compliance (r = 0.34, P = 0.01). Exercise decreased truncal fat percentage and waist circumference, suggesting a reduction of central adiposity, but did not significantly affect body weight and BMI. Exercise significantly reduced serum low-density lipoprotein cholesterol (P = 0.037), which was positively correlated with decreases of truncal fat percentage (r = 0.222, P = 0.048). No significant effects of interventions on insulin sensitivity, early insulin release index, and aerobic fitness were observed.</p><p><b>CONCLUSION</b>At least twice a week of one-hour after-school exercise significantly attenuated central adiposity and had a significant impact on lipid profiles in overweight Chinese adolescents.</p>

Effect of treadmill exercise and nutrition supplement on activity and gene expression of rate-limiting enzyme of heme metabolism and globin / 中国应用生理学杂志

<p><b>AIM</b>To investigate the possible role of rate-limiting enzyme of heme metabolism and globin in the development of the low hemoglobin (Hb), red blood (cell) count (RBC) and hematocrit (Hct) after long-term exercise, and effect of nutrition supplement on sports anemia.</p><p><b>METHODS</b>Male Wistar rats were randomly assigned to three groups (n = 10): control (C), exercise (P) and exercise + nutrition (G). Animals in the P and G groups started treadmill running at 30 m/min, 0% grade, 1 min/time. Running time was gradually increased with 2 min/time during initial 5 weeks and final 4 weeks. In addition, running frequency was 2 times/day except initial 2 weeks. At the end of eleventh week, gene expression of 5-aminolevulinate synthase (ALAS), ferrochelatase, alpha-globin and beta-globin in bone marrow were measured with RT-PCR. Mean-while heme oxygenase 1 (HO-1) activity in liver was measured with immunohistochemical method.</p><p><b>RESULTS</b>Eleven weeks of exercise induced a significant increase in HO-1 and a significant increase in gene expression of beta-globin (P < 0.01, P < 0.05, respectively). Treatment with anti-sports anemia compound dosage led to no significant differences in rate-limiting enzyme of heme metabolism and globin in the exercised rats. The G group had a significantly higher HO-1 level in liver than the C group (P < 0.01). These finds showed that exercise was associated with no significant difference in heme synthetase and alpha-globin gene expression, and significant difference in heme catabolic enzyme and beta-globin gene expression.</p><p><b>CONCLUSION</b>The increase of HO-1 activity in liver might be one of the causes of the lower Hb, RBC and Hct status in exercised rats.</p>

The effect of "living high and training low" on serum CK, LDH and ALT of rowing athletes / 中国应用生理学杂志

<p><b>AIM</b>To investigate the influence of living high-training low for 4 weeks on serum CK, LDH and ALT of rowing athletes.</p><p><b>METHODS</b>20 rowing athletes were divided into two groups: the one (ten subjects) spent 8-10 h per night in a tabernacle which was simulated altitude of 2 500 m in normobaric hypoxia (HiLo group), the another (ten subjects) slept at near sea level (control group). During the periods of test, all athletes were trained at the same relative or at the same intensity of work in normoxia state. The serum CK, LDH and ALT were measured at before, during 2 weeks, 4 weeks and 2 weeks after "living high and training low".</p><p><b>RESULTS</b>Baseline serum values for CK, LDH and ALT were not different between two groups (P > 0.05). The levels of CK, LDH of HiLo group were significantly increased (P < 0.05) than those of control group at 3 rd week, however, it was contrary at 5th and 7th week. After exercise of 2 km and 5 km, the values of LDH and CK at a moment notice and 30min postexercise test in HiLo group were significant lower than those in control group.</p><p><b>CONCLUSION</b>These results indicate that living high-training low may reduce the muscle damage associated with endurance exercise.</p>