It is well established in the literature that untrained individuals may improve their aerobic power with moderate to vigorous intensity continuous exercise training. For trained individuals, high intensity intermittent training (HIIT) has been shown to be beneficial for cardiac and, most importantly, muscular adaptations. Gibala and colleagues from the university of McMaster, Canada, developed a nice model of HIIT (Gibala et al., 2006). Last week I had the opportunity to watch the presentation by Professor Gibala during the congress of the European College of Sport Science at Bruges, Belgium. Professor Gibala showed data on the effect of 10 times 1-min bouts (95% of maximal heart rate) training on health. It is worth noting, however, that some athletes and especially non-athletes may not be able to sustain these 1-min bouts of high intensity. To increase compliance and consequently training-induced adaptations, Gunnarsson and Bagsbo (2012) from the University of Copenhagen presented the 10-20-30 training concept in a paper published this month in the Journal of Applied Physiology.
What is the training programme?
- The training programme consists of a 1.2 km warm-up at a low intensity followed by 3-4 times 5-min running with 2 min of rest between each bout. Each 5-min running period consists of repeated 30, 20, and 10 sec at intensities corresponding to <30%, < 60% and 90-100% of maximal intensity.
- Heart rate ranged between 82-87% of maximal in the 10-20-30 training group and averaged about 80% in the control group.
- Time spent at different heart rate zones were
80-85% max: 3min in the 10-20-30 and 12min in the control group (CON)
85-90% max: 6min in the 10-20-30 and 14min in CON
>90%max: 13min the 10-20-30 and 0min in CON
What they found
- VO2max increased in the 10-20-30 group but not in CON.
- Performance in a 1,500-m and a 5-Km run improved by 21 and 48 sec, respectively in the 10-20-30 group. No change was found in the CON group.
- Systolic blood pressure, total cholesterol and LDL were reduced in 10-20-30 but not in the CON group. These findings are of practical significance for at least two reasons. Firstly, other studies show no reductions in blood pressure with moderate intensity exercise in normotensive individuals (Dipla et al., 2012). Secondly, it is difficult to observe a significant lowering of total cholesterol levels with continuous sub maximal exercise at least in the majority of studies (Nassis et al., 2005). As Gunnarsson and Bagsbo (2012) state “…further studies are needed to examine the cause of these changes in blood cholesterol".
Take-home message
High-intensity intermittent running (alternating between 30-95% of maximal speed) might be a practical and time efficient tool to improve endurance performance, blood pressure and blood lipids.
Few issue for your consideration
1) To my opinion this training should compliment and not replace conventional training programmes. The reason is that we still now little about the effect of this programme on other aspects like muscle capillarization.
2) We don’t know what happens with well trained athletes.
3) Compliance is an issue especially in unhealthy population. Indeed t is very difficult, especially for untrained and non-healthy individuals, to run at 90-100% of maximal speed.
For more reading
Dipla, Nassis and Vrabas. Blood pressure control at rest and during exercise in obese children and adults. Journal of Obesity 147385, 2012.
Gibala et al. Short-term sprint interval versus traditional endurance training: similar initial adaptations in human skeletal muscle and exercise performance. Journal of Physiology 575: 901-911, 2006.
Gunnarson and Bangsbo. The 10-20-30 training concept improves performance and health profile in moderately trained runners. Journal of Applied Physiology 113: 16-24, 2012.
Nassis et al. Aerobic exercise training improves insulin sensitivity without changes in body weight, body fat, adiponectin, and inflammatory factors in overweight and obese girls. Metabolism 54: 1472-1479, 2005.
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