I'm a huge fan of the pool as a training tool and used it extensively whilst working at the English Institute of Sport.
Runners often find their chosen sport less attractive in the winter months, for obvious reasons. So if you're already shivering at the prospect or are injured and can't run on roads for a while, it may interest you to know that deep water running is a viable alternative.
In a joint study, researchers from England and Tasmania compared the effectiveness of deep water running and road running in improving maximum oxygen uptake in a group of 20 untrained young women.
After establishing baseline VO2max values, each participant was enrolled on a four-week training programme of either road running or deep water running, with progressive aerobic interval sessions carried out three times per week.
After four weeks, VO2max was retested and the women then embarked on 10 weeks of detraining before swapping training programmes for a further four weeks.
Both training programmes produced similar and substantial improvements in VO2max, and the researchers concluded that deep water running, in common with other aerobic activities, offers significant cardiovascular benefits when performed at the appropriate frequency (3-5 days per week), intensity (60-75% of maximum heart rate) and duration (20-60 minutes).
Journal of Strength and Conditioning Research, vol 14, no 2, pp191-195 Nick Grantham
Deep Water Training Option For Runners 10.31.2008