Experience From - Ruth Kessler , Larry ? , Larry Miller ,

Ruth Kessler

Anyone out there used Prohydrator during long runs or races? A friend of mine is running WS and is concerned about proper hydration and asked me if I would post this question to the list. Any positive or negative feedback would be appreciated.

Larry ?

I used the prohydrator and the pro-enhancer (choline) for training and during the Kettle Moraine 100 last year. The results were generally positive. I used the choline in the last half of the race and it seemed to have a good effect for me.

It was unseasonably cool at Kettle last year so I can't be sure how much the pro-hydrator helped.It certainly didn't hurt. I highly recommend using in training first to see how you react. Same with any product. The only negative effect I noticed was that I felt a little bloated at the start. I am also running Western this year but am uncertain if i will use the hydrator. I will use the pro-enhancer.

I seem to remember Karl King might have had a post on this subject earlier but I can't be sure. (If you read this post Karl and care to comment I value your opinion, even though I have disagreed with one or two) One thing for certain is that a proper hydration startegy is essential. It may very well be that the same effect can be achieved by proper pre-race hydration. I fully intend to also start out with CLIP (there you go Karl) I have no financial interest in any of the above products.

Larry Miller

I am not familiar with Prohydrator by brand name, but it sounds as if it may contain glycerol. If not, disregard this post. If so, then read on. Not knowing what the glycerol content is in the drink you specified, I'll discuss the value of glycerol only. Glycerol (or glycerin) ingestion increases the osmolarity of fluid in the blood and tissues. This causes the water consumed with glycerol to stay in the body until the extra glycerol is removed by the kidneys or metabolized (~4+ hours). In short, it aids in hyperhydration, particularly in the intracellular fluids, which will ultimately maintain plasma volume.

Most of the studies involving glycerol have used time to exhaustion at a fixed work load as the criterion for endurance enhancement. Generally, the improvement in time to exhaustion increased by ~20%. As it is unknown whether glycerol may be of some aid in higher intensity events (>60% VO2 max), a time to exhaustion test very much parallels the metabolic demands encountered in an ultra, except for the elite runners.

Generally, studies have used 0.5-1.5 g/kg glycerol, but most authorities suggest approximately 1-1.2 g/kg as an ideal dose. However, the quantity of water that must be ingested with glycerol is of some concern. From about 3 hours before an event up to about an hour before the event, one should ingest about 20-30 mL water/kg. For a 70kg runner, that's almost 2 liters in 2 hours!! If one takes higher doses of glycerol or ingests less water, i.e. there is a higher concentration of glycerol, headaches occur fairly commonly. This is because glycerol moves very slowly into the brain so osmolarity is much greater in the plasma than in the brain. This causes water to migrate out of the brain and cause headache. Finally, since most ultras last longer than 4 hours (see above), ingesting about 0.2g/kg with approximately 20-30 ounces water per hour will extend hyperhydration indefinitely (in theory anyway).

Most common side effects noted are headache, bloating, and diarrhea. Definitely try it in training before a race. I have a bottle sitting up on my refrigerator right now, but have not had the courage to give it a try. Maybe one day!