sighyoung wrote:Years ago, one of my friends was hospitalized for caffeine poisoning. He'd been ingesting so much (cups of coffee, diet Cokes, etc.) for so long (months or years) that he began having heart palpitations and had to go to the emergency room. He had to go cold turkey, and was a zombie for weeks. I don't think anyone here is close to that.
I dunno, if wart doesn't stop with the Mountain Dew enemas...
For endurance -yes. I think it can be overdone - but I always have caffeine before a race.
Caffeine and Athletic Performance
Despite considerable research in this area, the role of caffeine as a performance enhancing drug is still controversial. Some of the data are conflicting, which is in part due to how the experimental studies were designed and what methods were used. However, there is general agreement in a few areas:
1.Caffeine does not appear to benefit short term, high intensity exercise (eg. sprinting)
2.Caffeine can enhance performance in endurance sports.
Glycogen is the principal fuel for muscles and exhaustion occurs when it is depleted. A secondary fuel, which is much more abundant, is fat. As long as there is still glycogen available, working muscles can utilize fat. Caffeine mobilizes fat stores and encourages working muscles to use fat as a fuel. This delays the depletion of muscle glycogen and allows for a prolongation of exercise. The critical time period in glycogen sparing appears to occur during the first 15 minutes of exercise, where caffeine has been shown to decrease glycogen utilization by as much as 50%. Glycogen saved at the beginning is thus available during the later stages of exercise. Although the exact method by which caffeine does this is still unclear, caffeine caused sparing in all of the human studies where muscle glycogen levels were measured. The effect on performance, which was observed in most experimental studies, was that subjects were able to exercise longer until exhaustion occurred.
In addition to the beneficial effects on muscle, caffeine may alter the perception of how hard you are working. During testing, athletes are asked to judge their effort, which is referred to as the rating of perceived exertion (RPE). Some studies have yielded significantly lower RPE's -- less fatigue -- when the athlete used caffeine. Other studies have not found this effect. Obviously, the RPE is very subjective, and there are many things that may influence it.
I remember years ago there was a product called Water Joe; caffeinated water for the non-coffee drinkers. I don't know if it is still out there.
But when it first came out, intended as a substitute for coffee, they found out that people/offices were making coffee with the Water Joe! I think the company may have issued a statement or warning to not mix the two.
My health club has free coffee - good coffee too - and on my lifting days I get a cup and drink it while I work out. I've never seen anyone else do that - everyone has either water or these weird looking colored drinks. I'll go to water about half way in when I'm starting to get almost into a cardio workout, but to start it's coffee.
And then I take a travel mug and fill that guy up after I shower for my trip to work. It's probably 16 oz, I'll polish that off by 10 or so and then more often than not I get a mug of the crappy stuff at work. I always get one after lunch.
So I would say my daily coffee consumption would be 6+16+12+12 = 46oz/day.
I don't know if that's on the normal side or not but I suspect it's pretty high.
jim wrote:
So I would say my daily coffee consumption would be 6+16+12+12 = 46oz/day.
I don't know if that's on the normal side or not but I suspect it's pretty high.
I think my average is a similar amount, and my perception is that it's on the high side. Every once in a while, I try to scale back a little bit, but they I get busy with work, have to run on short sleep for a week or two, and I'm back up to previous levels.
I especially notice it on camping trips when it's more of a pain to make coffee in the middle of the day. That's when I feel like i have a caffeine problem.
According to this article, an average of 32 oz a day should be the max amount of coffee. While the article says that contradicts other studies, I think it's not an unreasonable amount to shoot for as a max.
jim wrote:
So I would say my daily coffee consumption would be 6+16+12+12 = 46oz/day.
I don't know if that's on the normal side or not but I suspect it's pretty high.
I think my average is a similar amount, and my perception is that it's on the high side. Every once in a while, I try to scale back a little bit, but they I get busy with work, have to run on short sleep for a week or two, and I'm back up to previous levels.
I especially notice it on camping trips when it's more of a pain to make coffee in the middle of the day. That's when I feel like i have a caffeine problem.
On our last trip, I realized some sort of instant coffe is in my future - esp now that I'm ready to take my oldest on a multi-day hiking trip next summer.
