Deep Water Running
Deep water running or aqua jogging is a tremendous form of cross training because there is no impact. Runners with almost any injury can safely continue their training in the water.
Deep water running or aqua jogging is usually performed in the deep end of a swimming pool. Most runners prefer to use a flotation belt. The belt allows you to focus on moving in a pattern similar to running, instead of how to keep your head above water.
You may find that interval training helps to break up the monotony of water running. Try three to four minute intervals of intense running followed by one to three minutes of rest.
The two studies conducted on deep water running showed that runners could maintain, but not improve running performance by training in the pool. Researcher at the University of Toledo, Ohio, tested competitive distance runners before and after four weeks of only deep water running. These athletes were able to maintain their 5K performance without running on land. Ed Eyestone, US Marathon Olympian, compared deep water running, cycling, and run training on run performance. After a six week period these “well trained” athletes maintained their 2 mile run time despite mode of training.
A new development in deep water run training is the aquatic shoe. I have not personally tried these yet but they look like they could really enhance the training experience.
"The AQx Aquatic Training Shoe ATS added resistance is 2-3 times depending on your velocity. Designed for both deep and shallow water training. The AQx "Intelligent Training" program is being adopted by World Class Athletes around the World."