Rule No. 8: Don’t be afraid to get in some brick workouts
Petersen will sometimes bring her trainer to the pool deck and do a hard 500M followed by 3 minutes hard on her bike. (She’ll do this three or four times in a row.) Or, she’ll do a bike-to-run workout where she’ll ride eight-to-10 minutes hard and then run a hard 1K off the bike, repeating this three to four times.