For example, I have to go to work at eight in the morning. If it is a morning run, I will warm up, stretch and take a bath, and the time will be tight, which will also affect the training effect. But from the physiological point of view, the body temperature is low in the morning, the muscle viscosity is high, the flexibility is poor, and the speed and explosive force will decrease; Hemoglobin and cardiopulmonary function are also not in the peak period, especially at 6: 00 in the morning when lung resistance and blood viscosity are the highest, so our maximum oxygen uptake will be relatively low.
But in the morning, the human body's ability of hormone secretion and metabolism is the strongest, and testosterone and cortisol, two important hormone indexes, are both high. Cortisol, in particular, is one of the strongest metabolic regulation hormones in human body. When the energy reserve and supply in the body are insufficient, especially when the sugar is insufficient, cortisol can promote the decomposition and energy supply of fat and protein, and convert them into sugar to maintain the sugar reserve. In other words, cortisol can mobilize the potential of long-term exercise and help improve the quality of long-distance aerobic training and marathon results. Therefore, it is more suitable to do low-intensity aerobic training in the morning, not too high-intensity anaerobic training, and the intensity of aerobic exercise should not be too high. It is best to control it within 75% of the maximum heart rate.
However, the peak of human muscle strength is at 17:00 ~ 19:00 in the afternoon, the peak of heart and respiratory function is at 18:00 ~ 19:00, and the peak of reaction speed and maximum speed appears around 17:00.
Moreover, at the end of the day, tissues and organs can enter the state of movement more quickly and can carry out high-intensity exercise quickly. Therefore, it is more suitable to do some "intensity training" in the afternoon or evening, such as interval running, lactic acid threshold running or strength training.