Exercise can sweat out the stress hormone to help last longer, but may consume too much testosterone and DHEA for weak erection. It all depends on the demand and supply of your testosterone and DHEA. Hard training will have the negative impact on erection for this reason.
Ejaculation discharge the bioelectric energy stored in the parasympthetic nervous system through the sympathetic function of the prostate, and burn out a lot of hormones - hGH, DHEA, testosterone and estrogen. Particularily, hGH, DHEA and testosterone are related to the elasticity and flexibility of your muscles and ligaments, and they, with estrogen, are associated with the regeneration of your cartilage of your joints.
Thus, your muscles and ligaments lack of hormones after ejaculation and become rigid and inelastic.
You should minimize your exercise activities and take a 20-30 minute nap to let your parasmypathetic and endocrine functions to recharge your body, after ejaculation.
We have tested this issue with our ViaGrowth-IV (item 1-005) in
https://actionlove.com/mail/herbform.htm
Taking 1 tablet of ViaGrowth-IV 1 or 2 hours prior to ejaculation, you feel nothing change on your felxibility and elasticity of your body. That is, you won't feel you have ejaculated before - you won't feel tired or exhausted at all, even in my 49-year-old body!
However, if you have a powerful orgasm with a woman and have a nice overnight sleep, you will feel stronger in the next day. Your and her orgasms must be powerful enough to stimulate the brain and endocrine system to produce more hormones.