The way to build base fitness without undermining technique is to bring both along at the same time.

This week’s workout comes from One-Hour Workouts: 50 Swim, Bike, and Run Workouts for Busy Athletes by Scott Molina, Mark Newton, and Michael Jacques.

Base work for swimming is a bit of a catch-22. You need to build endurance, which generally means mileage. But mileage can also bring fatigue, which can be counterproductive early in your swim buildup because with fatigue comes loss of technique, and technique is the most important factor governing your potential in the water. The way to build base fitness without undermining technique is to bring both along at the same time. In cycling and running we tend to start the season with lots of long, easy stuff. But in swimming you should start with slightly higher effort levels over shorter distances and gradually lengthen workouts as fitness and technique improve. The slowest you’ll ever race is Ironman pace, so that’s usually where you should start the season.

Building Endurance, Improving Technique

This is a session put together with the help of my good friend and protégé Gordo Byrn, who went from a guy who couldn’t swim 400 m without stopping to a 50-minute Ironman swimmer in 7 years. With discipline and dedication it is very possible to improve one’s swimming a great deal. Believe in the work!

Time/Distance Description

10 min.: Pyramid reps with bilateral breathing RPE 2 (5–10-sec. rest interval)
For example, 50/100/150…150/100/50 with rest between each
4 × 400 m: odd reps: 400 m freestyle with bilateral breathing RPE 2 (20-sec. rest interval)
even reps: 100 m IM/300 m freestyle RPE 3 (15-sec. rest interval)
Time remaining: Easy kicking and drills RPE 1

Remember that the goal of this session is to build endurance while improving your technique. If you feel yourself creeping to more than a steady effort, slow down. If you think that you need more rest during the main set, slow down.

When you’ve got more time, build the main set to 8 × 400 m.