Among Boulder endurance athletes many training variables are utilized to promote beneficial adaptations within our bodies.  These adaptations to the cardiovascular and musculoskeletal systems lead to improved future performances in practice and competitions.  One training variable includes interval training where athletes complete portions of endurance exercise at a high intensity followed by a recovery period.  As these intervals are completed, athletes are able to train at this intensity for a longer cumulative duration (multiple intervals) than if they tried to complete the same intensity and duration over a single bout.  High intensity interval training (HIIT) programs, where the intervals are held close to maximum efforts followed by recovery periods, are gaining momentum among endurance athletes.

A recent article in the Journal of Strength and Conditioning research examined the impact of HIIT programs among triathletes (Garcia-Pinillos et al. 2016).  Athletes were timed on a sprint triathlon before being divided into two groups: one continued their current triathlon training and the second continued their training except substituted their run training for HIIT.  Athletes in this group completed 3-4 sessions of HIIT/week consisting of 100m and 400m distances, as well as, 30-120 second run intervals over 5 weeks.  At the end of the 5 weeks all athletes were tested again on their sprint triathlon performance. 

The authors reported improved run and swim performance after the HIIT leading to faster times among the trained group.  This study adds evidence to support the use of high intensity, low volume interval training among endurance athletes.