Schneider, M., Dunn, A., & Cooper, D. (2009). Affect, exercise, and physical activity among healthy adolescents. Journal of Sport and Exercise Psychology, 31, 706-723.
Schneider, M. L., & Kwan, B. M. (2013). Psychological need satisfaction, intrinsic motivation and affective response to exercise in adolescents. Psychology of Sport and Exercise, 14, 776-785.
Antoniewicz, F., & Brand, R. (2016). Learning to like exercising: Evaluative conditioning changes automatic evaluations of 6 exercising and Influences subsequent exercising behavior. Journal of Sport and Exercise Psychology, doi:10.1123/jsep.2015-0125.
Interesting idea. Further research should be placed on whether the mood of an individual can determine future adherence to an exercise program. Studies of the central nervous system show that a negative experience tends to deter future encounters while positive associations encourage it. Nearly began my own review article on this topic but bowed out for another.
The endorphin has a potent analgesic action and to be released stimulates a sense of well-being, comfort, better mood and joy.
The production process and release of Endorphin by the pituitary gland occurs during and after physical activity.
There are people who are not so fond of exercising, but enjoy the sense of well being to have them done. Therefore, the release of endorphins that creates a sense of well being, causes this state of fullness experiencing regular practitioner of physical activity.
But this endorphin release depends on the characteristics of the physical activity that we are practicing. However, as it is a mechanism caused by the adaptation of the body to exercise, it is gradually released from the start of the activity.
At one point, however, this endorphin production reaches a threshold of production that makes it noticeable and arises wellness feeling that persists even after the end of the year.
Some studies claim that the effects of endorphin are felt up to an hour or two after their release. Other studies observed increase in this hormone dosages up to 72 hours after exercise.
The intensity and duration of exercise appear to be responsible for endorphin concentration in blood. After mild to moderate exercise (less than 60% of VO2 max) was not observed increased endorphin in the blood.