Why should I do VO2Max workouts

Long slow distance runs will help improving your aerobic capacity and trigger a variety of adaptations at cardiorespiratory level.

Research has however demonstrated that in order to improve maximum oxygen consumption rate, high intensity interval training will have significant positive impact.

These type of sessions consist of relatively short intervals at high intensity/pace with recoveries similar in duration (or shorter) than the intensity duration.  Intensity is above the anaerobic threshold.

By doing these type of workouts one is able to spend a longer period of time at maximal oxygen consumption rate (time at VO2Max) compared to constant speed workouts at VO2Max pace.

As a result impact of training adaptations specific to improving VO2Max - including also at mitochondrial muscular level (the muscle's power engines) - will be higher as one is capable of spending more time at maximal oxygen consumption rate.

Marathoners and Ultra-runners alike will therefore benefit from high-intensity interval training sessions.

These HIIT-sessions can be sub-divided into:

1. Short HIIT: sessions with intensity durations from 20 to 60 seconds (and similar recovery times)
   • eg 30":30" intervals are very common - often the interval repetitions are spread over 2 or 3 series
   • these workouts have the benefit that they have a lower lactate build-up
   • be careful though with accelerations and decelerations at start and end of the intervals as they may be more demanding at neuromuscular level
2. Long HIIT: sessions with intensity duration from 2 minutes to 5 minutes (and similar or shorter recovery times)
   • eg 3':3' intervals
   • as interval time is longer, and more time is spent above maximal lactate steady state pace (the pace where lactate production is equal to lactate consumption), there will be a higher level of lactate build up in these workouts 
   • research has shown however that these workouts tend to optimize time at VO2Max

Karel Sabbe tends to prefer the Long HIIT formats whereas Xavier Thévenard tends to use the Short HIIT formats more.

Both forms have shown significant positive impact on improving VO2Max.