High intensity interval training


The evidence is mounting for high intensity interval training on a number of fronts.

On September 29 2015 ABC Catalyst ran a segment titled Fit in 6 minutes a week, which explored the benefits of high intensity interval training. The regimen they advocated  for was high intensity exercise (uphill running, cycling with resistance, anything that involves maximum exertion) for 30 seconds at a time, with approximately 4.5minutes rest between intervals. The offered the best explanation so far for why we should be pursuing high intensity interval training; mitochondrial selection. The mitochondria are the powerhouses of our cells. Exercises that place extreme demands on the mitochondria effectively promote survival of  more efficient mitochondria and “weed out the duds”.

A common reason given for not exercising is time constraints,i and long term adherence to exercise programs is often less than 50% at 6 months.ii HIIT allows equal or improved outcomes for markedly less time investment and has the potential to be associated with higher rates of adherenceiii . In one study, similar changes were seen over a 6 week period in both HIIT subjects and CME subjects, although HIIT subjects performed only 20% of the exercise duration performed by the CME group v,  making it an extremely efficient intervention.

Next Step Physio will endeavour to make high intensity interval training available as an option for clients to explore when attending our classes, particularly those classes with a cardio component. Our circuit class structure allows for some flexibility in this regard, so the 30 second intervals can be carried out by willing participants when the circuit changeover occurs. Clients with cardiovascular or pulmonary disease should seek guidance from a specialist (cardiologist or respiratory physician) prior to commencing high intensity interval training.

Please take the time to watch the video before you decide if you wish to give it a go.


i. Trost SG, Owen N, Bauman AE, Sallis JF, Brown W. Correlates of adults’ participation in physical activity: review and update. Med Sci Sports Exerc 2002;34:1996–2001. Search PubMed


ii Thurston M, Green K. Adherence to exercise in later life: how can exercise on prescription programmes be made more effective? Health Promot Int 2004;19:379–87. Search PubMed


iii King AC, Haskell WL, Young DR, Oka RK, Stefanick ML. Long-term effects of varying intensities and formats of physical activity on participation rates, fitness, and lipoproteins in men and women aged 50 to 65 years. Circulation 1995;91:2596–604. Search PubMed



iv Bartlett JD, Close GL, MacLaren DP, Gregson W, Drust B, Morton JP. High-intensity interval running is perceived to be more enjoyable than moderate-intensity continuous exercise: implications for exercise adherence. J Sports Sci 2011;29:547–53. Search PubMed


v   Gibala MJ, Little JP, van Essen M, et al. Short-term sprint interval versus traditional endurance training: similar initial adaptations in human skeletal muscle and exercise performance. J Physiol 2006;575(Pt 3):901–11. Search PubMed