While shopping at my local vitamin shop I noticed they had pre workout supplements available. I took a quick look at them and they seemed to be designed to give you energy. All of them seemed to contain caffeine.
I'm going to address only the supplements that contain caffeine.
It appears that the use of caffeine in sports is a controversial topic. However there appears to be some base conclusions that are beginning to appear (emphasis mine):
Caffeine does not appear to benefit short term, high intensity exercise
Caffeine can enhance performance in endurance sports.
Taken from http://www.rice.edu/~jenky/sports/caffeine.html
In Caffeine and Athletic Performance, the author concludes that its effects vary by sport:
Pro:
It's been shown to improve endurance and time trial performance in cyclists, increase endurance in runners, and improve performance times and boost power in rowers. It’s also been shown to improve performance in cycling and running events lasting approximately 5 minutes, and to increase peak power output, speed, and isokinetic strength in sprint and power events lasting less than 10 seconds.
Con:
Specifically, caffeine has been shown to have no effect, and may even be a negative factor, in sprint and power events lasting anywhere from 15 seconds to 3 minutes.
A lot of people swear by caffeine saying that "improves" their workout. However I believe they merely enjoy the mental boost it gives them, aka more alert, rather than giving them a real, physical boost.
Special note about Caffeine and Creatine
I did come across an article that asserted that regular, high-doses of caffeine consumption interfere with creatine absorption!
I've personally tried a couple of products available on the market in New Zealand and I also was a big fan of using grape juice with creatine and dextrose/gluclose.
But after not using any pre-workout supplments for a month.. I've found no negating effects of just going in sober after an hour of my last meal.
I say don't bother with any caffeine pills or powders, if you're under 35 years of age you shouldn't be worried about energy performance anyways.
I've been taking this stuff called Ripped Juice. I'm not going to post a link because it's easy to Google.
I only take it 1-2 times a week before I expect to do a cardiovascular workout. Last Saturday I took it in the morning on am empty stomach and was able to do p90x then a solid 5k run with no stops. I feel like I'm more focused and consistent in my stride also. After the run, I felt like I could go back and do it again.
+1 for Ripped Juice but I wouldn't recommend taking it very often and I only take 1-2 depending on how long i'm going to be working out for. I would say go for 2 if you're not sensative to caffeine.
OBTW, it makes you feel f* amazing :)
