Exercise in the early morning is recommended as having a regular wake-up time helps set a regular daily cycle.
Also, taking some fresh air and working out facilitates the secretion of adrenaline, helping you start a new day more actively and easily.
However, the effectiveness of exercise itself is higher at night. Adrenocortical hormones and the thyroid stimulating hormone are known to be secreted more during night
workouts and increase the efficiency of exercise by boosting metabolism and waking up the body.
Exercise at night is also recommended if you are night owls.
However, if you are early birds, early morning workouts are better.
So, in short, this should be up to your individual life style.