physical health to increase stamina, increase sexual health strenght
Sexual health is partially, but strongly, tied to hormonal changes. But some medications and medical conditions can also be a factor. Both men and women experience declines in sex hormones in their 40s, but men see the sharpest declines. Studies have shown that heavy weight lifting of the larger muscle groups, legs, back and chest, increases testosterone. Also, hormone replacement therapy is also a good option and should be treated by a physician.
Stamina can be a factor as well. Improvements in cardiovascular endurance can help in the bedroom. However, excess endurance training may actually lower sex drive.