These max efforts do not have to be long - Tabata intervals typically last 60-90sec. but they have to be intense and uncomfortable - very uncomfortable. And, they don't have to be a part of every workout - you can include them in your swim/bike/run schedule 1-2x per week and you can even do them in the gym as part of your strength training program. Build them into your schedule gradually and consistently.
Everyone, from athletes to fitness enthusiasts to those looking to stay one step ahead of the grim reaper can incorporate these short bursts of all-out efforts to their training and experience the physical and mental benefits.
600yds. done as 100yds. swim/50yds. fast kick
6 x 50yds. odds = swim strong evens = easy choice
6 x 125yds. done as 50yds.easy swim/25yds.max effort/50yds.strong
6 x 100yds. strong on an interval that gives you 10sec. rest
4 x 25yds. kick max
4 x 50yds. done as 25yds. kick easy/25yds. swim max
4 x 50yds. easy kick