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Q: How long and in what situations are ice baths most appropriate? I tried and found that a 15-20 minute ice bath really helped my legs after struggling for 10 days to recover from a 50K race. The problem was a hypothermic response set in at 5 minutes after getting out of the bath that lasted for 30 minutes despite internal (hot drinks) and external rewarming!
A: I use ice baths all the time with my HS track kids and we go by these guidelines: 8 min at 50 F and only submerge up to your inner thigh. Eight minutes is more than enough to get the blood flowing through your legs, cleaning out all the crap in your legs and then bringing it back to be recycled/cleaned by your heart. 50F is more than cold enough, anything colder just "burns" And due to equipment constraints, we only can submerge to inner thigh. Check out this link on hit/cold therapy written by one of my asstant coaches: nackfortrack.blogspot.com
During the series of Master's races, I "iced" my legs within 1 hour post-race to help with recovery. I stood in the local river for 12-15 minutes, up to the tops of my thighs. I protected my feet from the frigid water (~40 deg F.) by wearing neoprene wading socks. I wore a heavy parka, warm hat, and gloves. Immediately after the cold water bath, I went home to a warm house, and was very comfortable. My legs did feel refreshed, and felt good during the next day's race. I did not need to use any external heat to warm my legs after the cold water bath.
One key is to have your legs only in the ice bath. You wear warm clothing on your chest/trunk, including even a down parka. You can drink warm fluids while in the bath, too.
Regarding the question on ice baths, I offer my personal experience, for what it is worth. I have used ice baths after marathon training runs that exceed 18 miles. After being in motion for more than two hours, I find that the ice bath is a critical part of my recovery. My practice is to stay in the ice bath for no more than 15 minutes. After the ice bath, I take a lukewarm-warm shower to warm up. I find that this shower does not negate the positive effect of the ice bath. I have not had problems with a hypothermic response after finishing the shower.
The recomendation is to use contrast baths from 50 degrees for one minute to 103 degrees for two minutes four times. I have used ice baths at 32 degrees (cold stream in winter) but for only for a max of one and a half minutes and then a hot shower and repeat three times. I don't doubt that staying in water at 32 degrees for 15-20 minutes would make one hypothermic, that's excessive.