FWIW, I came across an East German research of the athletes a few years back, and it found that having sex before competitions improved performance in female athletes, and decreased it in male athletes.
I would still recommend a maintenance run once a week before holding back in the bedroom, lol.
My Journal: http://www.marksdailyapple.com/forum/thread57916.html
When I let go of what I am, I become what I might be.
I would give up soccer long before the other that is for sure!
If you want to try the supplement route, I can personally say that spirulina before my workouts and habitually taking astaxanthin has made a huge difference. I dont really push myself to do anything long endurance...my workouts stop at about the 45min mark. However, after I started taking these two my capacity to sprint longer increased, I noticed a huge difference in the time it took me to break a sweat, had the feeling as though my lung capacity was better, etc. Overall, I feel like I need to push much harder to get that nice, glowing 'exhausted' feeling. It does wear off after a few months (the all powerful feeling), probably because I have stayed on these for the last 11 months straight and need to cycle off of them. I dont want to though...such a noticeable difference it made for me, and I know there's all kinds of other health benefits to the supplements.