Boost Your VO2Max: Key Swim and Run Workouts for Serious Gains

Contributed by Jonathan Barber
Jonathan is a former professional triathlete and cyclist. He studied exercise physiology at Stanford University School of Medicine and is a USA-certified coach in swimming, cycling, and triathlon. The views expressed in this article are his own. For expert article submissions, email: [email protected].

Do you want to get faster?

I know I do. But we may have to do a bit of suffering first.

Why is it that some athletes are just so much faster than others? How can they move so efficiently, so relaxed — while many of us struggle at a much slower pace?

There are many factors that contribute to an athlete’s ability to swim or run fast. One of the key factors is a measurement called VO2Max. The higher your VO2Max, the higher your aerobic power.

Your VO2Max is the measurement of how much oxygen your body can effectively use to produce energy during exercise. Specifically, it refers to the amount of milliliters of oxygen the body can use per kilogram of body weight every minute.

Put simply — the faster your body can use oxygen, the faster you can swim or run.

Of course, you need to have the other basics in place — strength, good technique, fitness, conditioning, and experience. But you’ll notice that some people who haven’t run in years can still show up and run a super-fast 5K. That’s because they’re blessed with a naturally high VO2Max.

Our VO2Max limit is genetically determined, but that doesn’t mean we can’t train to raise our current level closer to our genetic ceiling.

For example, I may have a VO2Max of 50 ml/kg/min today, but my genetic limit might be 70+. With the right training, I can move closer to my potential.

How Can We Train to Boost VO2Max?

Let’s say your comfortable running pace is 8 minutes per kilometer. If you always run at 8 min/km, you won’t get significantly faster. You may gain endurance over time, but you won’t come close to your full potential while training at a comfortable pace every day.

The truth is, training at varied intensities is what produces results.

In my experience, most triathletes rarely train above 80–85% of their maximum effort. Training at that effort has value — it represents the upper limits of aerobic ability and helps build endurance.

But training at or near your VO2Max — the intensity where your body is consuming oxygen at its highest possible rate — is what pushes your aerobic capacity to new levels. And the higher your aerobic capacity, the greater your endurance performance will be.

Training this hard isn’t easy. It’s mentally and physically uncomfortable. What helps is understanding why you’re pushing so hard — and having a clear reason to do it. I always keep my goals in mind. What’s yours? A personal best? Beating your training buddy? Qualifying for Worlds?

Hold that goal in your mind. The pain will be easier to endure.

What Workouts Boost VO2Max?

There are three types of workouts that best increase VO2Max:

1. 20 to 30 short, high-effort intervals with minimal rest
2. 6 to 8 near-max efforts over 60–90 seconds with short recovery
3. 3 to 4 efforts of 4 minutes at near max, with 1:1 rest ratios

Sample Swim Workouts

These are very tough sessions. Build up gradually if needed.

1. 20–30 x 50m at 90–95% effort, 7–10 seconds rest
2. 6–8 x 100m at 95% effort, 20–30 seconds rest
   – Advanced: increase to 150m with same intensity and rest
3. 3–4 x 300m at 90–95% effort, with 1:1 active rest
   – Example: If 300m takes 5 minutes, rest for 5 minutes. Stay active between intervals.
   – Beginners: start with 300m + 200m + 100m using the same effort and rest structure

Sample Run Workouts

1. Up to 20 x 200m at 90–95% effort, with 100m jog recovery
   – Keep total rest under 30 seconds — shorten the jog if needed
2. 6–8 x 400m at 95% effort, 60 seconds rest
3. 3–4 x 1000m (or 1200m for advanced runners) at 90–95% effort, with 1:1 active rest

Final Thoughts

Training to boost your VO2Max is just one part of a well-balanced program — but it’s a critical one. It brings you closer to your peak potential.

Long runs, distance swim sets, threshold efforts, and easy days are all still important. But if you want to make real progress, you need to train at efforts close to your limit — not just stay within your comfort zone.

Do the hard thing. Embrace the suffering. And enjoy the results that follow.