This plan takes a more aggressive approach than the Level 1-3 plans do to developing your fitness within the parameters of 12 weeks of training, 6 workouts per week, and a modest initial fitness level.

The plan is designed to prepare you to successfully complete a sprint triathlon in 12 weeks. It entails just one workout per day, six days per week: two swims, two rides, and two runs. (There’s a third weekly run in weeks 8 and 10, where Saturday’s ride is replaced with a bike-run brick workout.)

The Level 4 plan is divided into three phases. Weeks 1-3 constitute the base phase; the next four weeks make up the build phase; and the last five are the peak phase. Weeks 4 and 8 are recovery weeks, with slightly reduced training to give your body a chance to absorb recent training and prepare for the harder workouts to come. Week 12 – race week – is a taper week, meaning your training tapers off during the week to ensure you’re rested and ready to perform on race day.

The plan begins with a total of 2,100 yards of swimming, 1 hour and 30 minutes of cycling, and 50 minutes of running in Week 1. It peaks with 3,450 yards of swimming, 3 hours of cycling, and 1 hour and 37 minutes of running in Week 11.