How to improve maximal oxygen uptake (VO2 max)?

From the Guidelines

To improve VO2max, focus on consistent high-intensity interval training (HIIT) and longer endurance workouts, as evidenced by the most recent study 1, which suggests that higher-intensity exercise may be required to elicit clinically significant increases in maximal oxygen uptake. Incorporating HIIT sessions 2-3 times weekly, alternating between intense efforts (80-95% of maximum heart rate) for 1-4 minutes and recovery periods (60-70% maximum heart rate) for similar durations, can lead to significant improvements in VO2max. Complementing HIIT with 1-2 weekly longer, steady-state cardio sessions lasting 45-90 minutes at moderate intensity (65-75% maximum heart rate) can further enhance aerobic capacity. Progressive overload is essential, with gradual increases in workout duration, intensity, or frequency every 2-3 weeks, to continue challenging the cardiovascular system and promoting adaptations. Activities that engage large muscle groups, such as running, cycling, swimming, or rowing, are ideal for maximum oxygen utilization. Allowing adequate recovery with at least 48 hours between high-intensity sessions and ensuring proper nutrition with sufficient carbohydrates to fuel workouts and protein for recovery are crucial for optimal performance. Proper hydration before, during, and after exercise is also vital for maintaining exercise intensity and supporting overall health. VO2max improvements typically become noticeable after 4-6 weeks of consistent training, with potential increases of 5-30% depending on starting fitness level, genetics, and training adherence, as supported by earlier studies 1. These improvements occur because regular cardiorespiratory training enhances the heart's stroke volume, increases capillary density in muscles, and improves mitochondrial function, all contributing to better oxygen delivery and utilization during exercise. It is essential to note that individual responses to exercise training may vary, and factors such as age, fitness level, and health status should be considered when designing an exercise program to improve VO2max. However, the available evidence suggests that a well-structured exercise program incorporating HIIT and endurance training can be an effective way to improve VO2max and overall cardiovascular health, even in patients with certain health conditions, such as hypertrophic cardiomyopathy 1.

From the Research

Improving VO2max

To improve VO2max, several studies suggest the following methods:

• High-intensity interval training (HIIT) is an effective way to improve VO2max, as seen in studies 2, 3, 4, 5, 6
• Aerobic high-intensity intervals are superior to sprint intervals in improving VO2max, as shown in a study 2
• HIIT can be performed with different protocols, such as 4 x 4 min of interval running at 90-95% maximal heart rate, with 3 min of active resting at 70% maximal heart rate 3
• The duration and intensity of HIIT can vary, but longer intervals (≥2min), higher volumes (≥15min), and moderate to long-term training (≥4-12weeks) tend to have larger effects on VO2max 5

Key Findings

Some key findings from the studies include:

• HIIT can improve VO2max by 5-7% in 8 weeks, as seen in a study 3
• The improvement in VO2max is related to baseline VO2max and fatigue index, as shown in a study 6
• HIIT can also improve stroke volume, oxygen pulse, and power output, as seen in studies 2, 3, 6
• The effects of HIIT on VO2max can vary depending on the population, with larger effects seen in healthy, young to middle-aged adults, as shown in a study 4

Training Protocols

Different training protocols can be used to improve VO2max, including:

• 4 x 4 min of interval running at 90-95% maximal heart rate, with 3 min of active resting at 70% maximal heart rate 3
• 15/15 interval running, with 15 s of running at 90-95% maximal heart rate, followed by 15 s of active resting at 70% maximal heart rate 3
• Short-intervals (≤30s), low-volume (≤5min), and short-term HIIT (≤4weeks) can be effective for developing VO2max, especially for the general population, as shown in a study 5