Training to Improve VO₂ Max in Runners

VO₂ max, or maximal oxygen uptake, is one of the most critical physiological markers for endurance performance. It represents the maximum amount of oxygen an individual can utilize during intense exercise. A higher VO₂ max allows runners to sustain faster paces for longer durations before reaching fatigue. This article explores the scientific foundations of VO₂ max, its determinants, and a set of workouts to enhance it effectively.

The Science Behind VO₂ Max

VO₂ max is influenced by multiple physiological factors:

• Cardiac Output: The amount of blood the heart pumps per minute. Blood carries oxygen from the lungs to the muscles. The more blood you pump, the more oxygen you transport.
• Capillaries: These are tiny blood vessels where oxygen can leave the blood and enter the muscles. More capillaries means more places where oxygen can make the jump. Additionally, muscles can become more efficient at extracting the oxygen out of the blood.
• Mitochondria: These energy factories in the muscle cells will convert oxygen into energy. The more mitochondria you have, the more oxygen you can turn into energy. Additionally, increasing the efficiency of these factories will also increase energy output.

Common Misunderstandings About VO₂ Max Training

One of the most prevalent misconceptions about improving VO₂ max is the belief that only "VO₂ max-specific" workouts, such as high-intensity intervals, contribute to its development. While interval training is a crucial component, it is far from the only factor that influences VO₂ max improvements. Several additional training methods play an integral role:

• Easy Runs build your aerobic base, which increase the number of capillaries and mitochondria, setting the foundation for higher VO₂ max gains.
• Tempo Runs and Lactate Threshold Training build on the same adaptations as easy runs, but with greater intensity and specificity. They also increase your ability to handle higher aerobic loads for longer periods of time.
• Hill Sprints challenge both cardiovascular and muscular systems, primarily stimulating neuromuscular power and muscle recruitment. They improve running economy and support the workouts that target VO₂ max development.

Don't Forget Recovery and Adaptation: Many athletes mistakenly believe that more high-intensity work leads to faster improvements. However, adaptation occurs during recovery, and excessive intensity without proper rest can lead to overtraining and stagnation.

Understanding that VO₂ max development is a multi-faceted process allows runners to adopt a more holistic and sustainable training approach, incorporating various types of workouts rather than focusing solely on high-intensity intervals.

Note: VO₂ max can improve with training—especially in beginners—but factors like genetics, age, and training history also play a role. Fortunately, you don’t need the highest VO₂ max to be a strong runner. What matters most is training consistently and intelligently.

Using COROS to Find Your VO₂ Max Training Pace

VO2 Max training happens in Pace Zone 5: Anaerobic Endurance on your COROS watch. This is a high-intensity pace, usually where you’re breathing hard and can only hold the effort for 10-12 minutes.

To make sure you’re training in the right zones, complete a Running Fitness Test on your COROS watch. It updates your personal pace and heart rate zones so your workouts match your fitness level.

COROS Education: We use a 6-zone model for your threshold pace and heart rate zones. For more info about how COROS calculates your zones, check out our article on pace zones.

VO₂ Max Workouts

These workouts are designed to improve VO₂ max and can be adjusted based on experience level. Click to view & download each workout:

• Short Intervals
• Long Intervals
• Hill Repeats
• Mixed Tempo and VO₂ Max Work
• Fartlek-Style VO₂ Training

Scaling Workouts Based on Experience

• Beginners: Start with fewer repetitions and longer recovery times.
• Intermediate Runners: Increase the number of repetitions and reduce recovery times gradually.
• Advanced Athletes: Maximize total volume and minimize recovery to elicit the greatest physiological adaptation.

Listen to Your Body

Some days your Zone 5 pace might feel too hard or too easy. That’s normal. Things like heat, altitude, or stress can affect how your body responds. During VO2 Max workouts, use how you feel as a guide. You should be breathing heavily and working very hard, but not quite at maximum effort or out of control.

Monitoring breathing patterns alongside perceived exertion (RPE) can help runners gauge effort and make real-time adjustments. These are often superior metrics to training pace, as they are more in tune with what your body is actually going through. While pace provides structure, the most adaptable and reliable training cues, especially in variable environments, are your breathing and perceived effort.

Improving your VO2 Max takes the right mix of intensity, recovery, and consistency. Use your COROS watch to track pace zones, monitor progress, and guide your training. Most importantly, stay in tune with your body and give yourself time to adapt.