This book puts a little spice to your leisure monotonous sessions. The sessions are in 4 versions: short sessions (40min) to very long (1h45) and imposing you a minimum of 2 sessions per week will progress you taking pleasure. I found myself eager to jump into the water! Be careful though, you have to crawl (say 50m mini 100m but would be better), breaststroke and backstroke. The drives then gradually guide you to the butterfly stroke.
