Can you currently swim 1,500 meters, bike 30 miles, and run 5 miles without much drama? If so, you already have the base fitness for a Half Distance Triathlon and begin the Senior Triathletes 60+ Half Distance Triathlon Plan. The harder question for athletes 60 and older isn't whether you can do the work. It's whether you can do the work without it costing you weeks of recovery, or worse, an injury that costs you the season.