(12-19-2013) Interval training is increasingly done to improve endurance or lose weight effectively. Research has shown that it is more effective in those areas than regular endurance training at moderate intensity. There are however different forms of interval training. Researchers from the Japan Aerospace Exploration Agency and the Universities of Tsukuba and Kyoto have performed a study in which the effects of interval training using two different protocols are compared to endurance training at a moderate intensity.

What did the researchers do?

The researchers recruted 42 healthy inactive men. The subjects were divided into three groups: The Sprint Interval Group, the Aerobic Interval Training Group and the Continuous Endurance Group. All three groups performed their respective training protocols on five times a week for eight weeks on a stationary bicycle. The Sprint Interval Training consisted of a 2 minute warm up after which seven 30 second sprints were performed alternated with 15 seconds of rest. Sprint training intensity was set at 120% of maximum oxygen uptake (VO₂max). The Aerobic Interval Training protocol consisted of the same 2 minute warm up followed by three spirtins of three minutes each at 80-85% VO₂max alternated by two minute rest periods at 50% VO₂max. The Continuous Endurance Training protocol consisted of a 2 minute warm up followed by 40 minutes of cycling at 60-65% VO₂max. Before and after the eight week training period a maximum oxygen uptake test was done. In addition, an MRI scan of the heart was made to see if the changes in endurance were caused by an increase in the mass of the left heart chamber (left ventricle).

What where the results?

The results are depicted in the figures below:

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Relative changeafter 8 weeks	Sprint Interval Training	Aerobic Interval Training	Continuous Aerobic Training
VO2Max:	16.7%	22.5%	10.0%
Lef Ventricular Mass:	6.5%	8.0%	2.5%

 

After eight weeks of training all groups had increased their VO₂max. There was however a large difference between the Aerobic Interval Training group and the Continuous Aerobic Group. Both interval training groups showed similar increases in left ventricular mass. The Continuous Aerobic Training group did not have a significant increase in left heart chamber mass.

What did the researchers conclude?

The researchers concluded that all three training protocols were effective in increasing VO₂max, but the Aerobic Interval Training was particularly effective. Although left ventricular mass increased in both interval training groups, it could only explain a small part of the increase in VO₂max and other factors are likely to play a larger role in heart chamber mass.

What does this mean for me?

-To increase endurance 10 minutes of interval training is more effective than 40 minutes of continuous aerobic training.

-Aerobic interval training consisting of three minute sprints at 80-85% VO₂max is more effective in increasing endurance and VO₂max than 30 second sprints at an intensity of 120% VO₂max.

See also:

-Cardio training for weight loss

-How to lose weight and fat effectively

Reference:

-Matsuo, T., Saotome, K., Seino, S., et al. Effects of a Low-Volume Aerobic-Type Interval Exercise on VO2max and Cardiac Mass. Medicine & Science in Sports & Exercise 2014, 46, 1, 42-50.