In order to bring you the best possible user experience, this site uses Javascript. If you are seeing this message, it is likely that the Javascript option in your browser is disabled. For optimal viewing of this site, please ensure that Javascript is enabled for your browser.
Did you know that your browser is out of date? To get the best experience using our website we recommend that you upgrade to a newer version. Learn more.

We use cookies to optimise the design of this website and make continuous improvement. By continuing your visit, you consent to the use of cookies. Learn more

Quick but effective - Can very short all-out interval training protocols overcome time constraint on adhesion to regular exercise?

Comment by Nicolle Kränkel, EACPR Exercise, Basic and Translational Research Section


Time constraints are often among the chief reasons for physical inactivity – a major behavioural risk factor to tackle for reducing overall mortality from non-communicable diseases, second only to reducing alcohol consumption in the current WHO report [1].

The group of Gillen et al. therefore tested whether a 10-minute interval cycling protocol, was comparable to a “traditional” 45-minutes moderate-intensity continuous exercise protocol for improving peak oxygen uptake, glucose uptake, and body composition [2].

The interval protocol consisted of three 20-second “all-out” bouts alternated with 2-minute blocks of low-intensity cycling at 50W. The continuous protocoll consisted of 45 minutes of cycling at ca. 70% of the individual´s maximal heart rate. Both groups exercised three times per week for a duration of 12 weeks [2].

Maximal oxygen uptake, glucose uptake and body fat content were improved after both exercise interventions as compared to a sedentary control group [2]. Improvements in functional parameters were supported by enhanced expression of respiratory chain proteins and citrate synthase, assessed in skeletal muscle biopsies [2]. The study thus supports the notion that a 10-minutes interval training protocoll, containing 3 short “all out” bouts, is at least not inferior to a 45-minute programm of continuous cycling in improving physical fitness and glucose metabolism. While intra-individual changes where significantly greater in both exercise groups than in the sedentary control, group sizes appear rather low to observe differences between both exercise protocols.

Higher powered studies might therefore be necessary to ascertain whether interval training protocols with short bouts of high-intensity exercise might help to overcome time constraints, the main perceived barrier to living a physically active life and thus improve long-time cardiovascular risk. This also includes assessment of long-term adherence, in order to understand whether time is a real or rather perceived barrier to regular exercise training.

Note: The content of this article reflects the personal opinion of the author/s and is not necessarily the official position of the European Society of Cardiology


1. WHO. Global status report on non-communicable diseases, World Health Organization, Geneva, Switzerland (2014) (ISBN 978 92 4 156485 4)

2. Gillen JB, Martin BJ, MacInnis MJ, Skelly LE, Tarnopolsky MA, Gibala MJ. Twelve Weeks of Sprint Interval Training Improves Indices of Cardiometabolic Health Similar to Traditional Endurance Training despite a Five-Fold Lower Exercise Volume and Time Commitment. PLoS One. 2016;11(4):e0154075. doi: 10.1371/journal.pone.0154075.

Notes to editor

Nicolle Kränkel, Charité – Universitätsmedizin Berlin, Berlin Germany