By the Numbers

The Numbers

A few years ago I was involved with a cycling study on campus that involved doses of placebo/caffeine in cool/warm climates. This testing required gathering some normalized data, which I can share...

Keep in mind, these numbers are two years old, but VO2 doesn't vary all that much.

-VO2 Max: 4.6 L/min
-VO2 Max (normalized): 58.5 ml/kg/min
-Estimated Heart Stroke Volume: 125 ml
-Estimated Lactage Threshold: 65% LT <<< I am going to get this retested, he wasn't testing specifically for LT

The following pertained specifically to the nature of the study, but are still interesting.

Wattage at 60% VO2 Max: 170
Wattage at 70% VO2 Max: 210
Sweat Rate at 11 degrees C: .8 L/hr
Sweat Rate at 33 degrees C: 1 L/hr

The Study:

We were placed in a temperature controlled room with a stationary bike that can constantly vary it's wattage. So, rather than provide x resistance at your given cadence/gear ratio, it will provide x resistance...whenever. Pretty cool, and also the most realistic road feel on a trainer I've felt. I think it cost something like $10,000. And to ruin it, they had a Fizik Arione saddle...

Anyway, we sat on the bike for 1.5 hours, alternating every 15 minutes between the 60 and 70% wattages, to fatigue us. We then performed a 15 minute TT, when we were supposed to go as fast as possible. We did this 4 times-two times at 11 degrees, twice at 33, once each time with caffeine, one with a placebo.

Two kickers-we had a cathiter in our arms to pull blood every 15 minutes (they were nice enough to put plasma back in each time), and we they were constantly monitoring our core temperature, for, we were told, safety during the trial. That safety measure in labs requires a probe up the pants. Not cool.

When the results first came out, I was very suprised. My average wattage from placebo to caffeine in 11 degrees showed a 3.4% improvement (297 to 308 watt average), while in 33 degree heat it jumped an amazing 29.4% (200 to 258 watt average). I was later told that the difference in heat was minimal with everyone else, so I'm assuming I just had a real bad day with the placebo in the heat. Too bad, I was ready to start chugging espresso before any hot day.

The absolute, god awful worst part was the stroke volume testing. We had the regular VO2 tester mask on, with the input and output air disconnected, so we would breathe in and out of a bag of air for about 20 seconds. And he made us take constant, really deep breaths. Picture breathing in and out of a plastic bag on a ride. Not fun. I also have no idea how it works, but I assume it has something to do with calculating the Co2 in the bagged air, and running that through some #'s to hit a stroke volume. I also have no idea what pertinence that information had to the study.

Best part? The first 30 minutes of each 33 degree study. It was February at the time, so it was AWESOME to go into a hot chamber and be warm for a half hour.