"I appreciate I'm getting my info from something I saw on the telly last week, but I thought that HITT actually increased VO2 max in only 25% of the sample? That would tend to suggest it's not necessarily the best training method for the majority. "
No - Horizon did a rubbish job of explaining this.20% of people are genetically predisposed to a lack of improvement in VO2max from this type of training.They still get the benefits of improved insulin response, running economy, power development (wattage produced) though.4 in 5 people get the full benefit. 1 in 5 get significant benefit, but not quite as much.
http://jap.physiology.org/content/107/6/1771.short - this one's frustrating - they talk about 'long term' improvements, but what they mean is improvement in longer-duration events - ie training for 10ks using 30sec intervals. The perils of writing science in languages other than native!
"The major findings of the present study were that inclusion of speed endurance training with a reduction in training volume not only resulted in improved short-term work capacity but also increased 3- and 10-km performance in endurance-trained runners. The improvements were associated with an ∼70% higher expression of Na+-K+ pump α2-subunit and lower plasma K+ concentrations during exhaustive running.
An amazing finding of the present study was that performance of these well-trained runners in the 3- and 10-km trials was significant elevated as a result of the speed endurance training and reduced amount of training. Furthermore, that six of the runners in the SET group at the end of the IT period made their best 10-km time ever with an improvement of >1 min, despite having been running for >5 yr and performing >20 10-km runs. These observations suggest that speed endurance training is a powerful stimulus to improve performance even in an event lasting >30 min despite that the duration of each exercise bout was 30 s."
Not bad for 10mins research! Going for a swim now.
In terms of how to do it, one of the most influential studies (tabata) did the following:
- easy warmup
- Eight repeats of 20seconds flat-out sprint, followed by 10seconds walk recovery.
- easy warm down.
It takes 4 minutes, it's really hard work and you're flat-out sprinting which will improve long-term aerobic endurance, VO2max, glucose tolerance and will burn more fat than any other approach to running. It also improves running economy as you can't run flat-out without running properly.
I do 3 sessions per week: one session as per above, one session of 5 repeats of 3mins fast, 90sec walk and one session of 5 repeats of 5mins fast, 2min walk. I run 14 miles per week on average and my 10k time came down last year from 39mins to 36mins.