The Effects of Ground and Treadmill Running on Energy Metabolism and Muscle Contractile Properties:A Randomized Cross-Over Study

Purpose This study aimed to compare the effects of ground and treadmill running on energy metabolism and muscle con-tractile properties,providing a basis for the general public to choose running venues.Methods Ten male college students(age,20.10±1.53 years;height,176.20±5.49 cm;weight,72.14±8.25 kg;body fat percent,12.41%±4.65%)were recruited in this study.Energy expenditure(EE)was measured using the accelerometer(GT9X)combined with specific estimation equations.Average heart rate(HR)was measured using a heart rate band(Polar).Muscle contractile properties were assessed by measuring muscle displacement(Dm)and contraction velocity(Vc)using tensiomyography(TMG-S1).Blood glucose(Glu)and lactate(Lac)were measured by portable devices(eB-G and Lactate Scout).The running speed was 9 km/h and the duration was 25 min.Two-way ANOVA(protocol×time)was used to analyze the effect of running protocols on energy metabolism and muscle contractile properties.Results EE of treadmill running was significantly higher than EE of ground running(protocol main effect,P<0.001),and HR of treadmill running was significantly higher than that of ground running in the first testing time(protocol simple effect,P=0.026;protocol×time interaction P=0.043).The decrease in Dm of the rectus femoris after treadmill running was significantly higher than that of ground running(protocol main effect,P=0.009).The interaction of different running protocols and testing times on Lac was significant(P=0.025),but all results of the simple effects analysis were not statisti-cally significant(P>0.05).Conclusion Our study found a difference in energy expenditure between treadmill and ground running at 9 km/h with duration of 25 min.In addition,treadmills are more likely to cause a decrease in muscle displacement distance of the rectus femoris measured after exercise than ground running.Future studies are needed to further investigate whether the differences are induced by internal metabolism or the environmental conditions of running.

Paternal physical exercise modulates global DNA methylation status in the hippocampus of male rat offspring

It is widely known that maternal physical exercise is able to induce beneficial improvements in offspring cognition; however, the effects of paternal exercise have not been explored in detail. The present study was designed to evaluate the impact of paternal physical exercise on memory and learning, neuroplasticity and DNA methylation levels in the hippocampus of male offspring. Adult male Wistar rats were divided into two groups: sedentary or exercised fathers. The paternal preconception exercise protocol consisted of treadmill running, 20 minutes daily, 5 consecutive days per week for 22 days, while the mothers were not trained. After mating, paternal sperm was collected for global DNA methylation analysis. At postnatal day 53, the offspring were euthanized, and the hippocampus was dissected to measure cell survival by 5-bromo-2′-deoxiuridine and to determine the expression of synaptophysin, reelin, brain-derived neurotrophic factor and global DNA methylation levels. To measure spatial memory and learning changes in offspring, the Morris water maze paradigm was used. There was an improvement in spatial learning, as well as a significant decrease in hippocampal global DNA methylation levels in the offspring from exercised fathers compared with those from sedentary ones; however, no changes were observed in neuroplasticity biomarkers brain-derived neurotrophic factor, reelin and 5-bromo-2′-deoxiuridine. Finally, the global DNA methylation of paternal sperm was not significantly changed by physical exercise. These results suggest a link between paternal preconception physical activity and cognitive benefit, which may be associated with hippocampal epigenetic programming in male offspring. However, the biological mechanisms of this modulation remain unclear.