Effect Of The Circadian Rhythm On Relevant Indicators Of Energy Metabolism During Walking And Jogging

Objective:This article takes young people as the research object,to observe the changes of the related indexes of energy metabolism in the walking/running of the circadian rhythms,to explore the regularity of circadian rhythm of exercise energy metabolism and the dependence on the intensity of exercise,to provide theoretical basis for further study on the change law of exercise energy metabolism,and to provide the theoretical basis for the value mining of fitness walking/running.Methods:Tests include indicators in resting state and indicators in motion.Resting state to take supine position,the state of movement for the treadmill.The speed of the treadmill is: 3.2km/h,4.8km/h,6.4km/h and 8.0km/h,each speed test 6min,rest 10 min between each speed,according to the actual situation of the subjects,the heart rate at the end of each speed return to the level of quiet and then the next speed test.Using a height-weight gauge to measure height and weight,the body composition of the subjects was measured using bioelectrical impedance methods,and the Cortex Metamax 3B to test the gas metabolic indices in resting and moving states.Test indicators are: height?cm?,weight?kg?,BMI?kg/m2?,HR?secondary/min?,blood pressure?mm Hg?,VO₂?L/min?,VCO₂?l/min?,RER,VE?l/min?,METS,EE?kcal/h?,BF?Secondary/ min?.Each subjects repeated 3 times under the same test conditions,3 tests were selected for three different time periods,morning?9:00-11:00?,afternoon?15:00-17:00?and evening?19:00-21:00?,in order to avoid the impact of the last ex periment on the next experiment,The interval between two experiments was over 24 h.Results:?1?The resting heart rate was the highest in the evening and the low est in the morning.There was a statistically significant difference between the quiet heart rate in the morning and the evening?P=0.029<0.05?.There was no significant difference in systolic blood pressure,diastolic blood pressure and pulse pressure in three time periods.VO₂ and VCO₂ were the highest in the morning and the difference was statistically significant in the morning and evening.?VO₂,P=0.04<0.05;VCO₂,P=0.02<0.05?.BF and RER were higher in the evening than in the morning and afternoon,and the difference was not statistically significant.EE and METS were the lowest in the morning and the highest in the evening.The difference was very significant?METS,P=0.002<0.01,EE,P=0.003<0.01?.?2?Heart rate increases with the increase of exercise intensity,and the heart rate at the same intensity at three time periods is higher than the other two periods,and with the increase of exercise intensity,the difference gradually decreases.With the increase of movement speed and the increase of movement intensity,VO₂,VCO₂,BF,METS and EE showed an increasing trend.In the whole day,the time period of different time was higher than that in the morning and afternoon.RER was higher than that of the exercise state in resting state,and the exercise with high intensity was greater than that with low intensity.Conclusions:?1?In the resting state,the energy metabolism showed an obvious circadian rhythm.In one day,the night was higher than the other two period?2?Under the condition of exercise,the influence of circadian rhythm on energy metabolism index gradually decreases with the increase of speed of fitness walking.?3?The effect of exercise intensity on energy metabolism is greater than the circadian rhythm.?4?Choice of exercise time and intensity: according to the change of energy metabolism index in three time periods,it should be appropriate to exercise at night,but the choice of place should be paid attention to.The strength of fitness walking should be moderate in strength.