PMID 28391489

Research
All papers

Research into the Health Benefits of Sprint Interval Training Should Focus on Protocols with Fewer and Shorter Sprints

Vollaard NBJ, Metcalfe RS

Question

Should research on sprint interval training shift from classic 4-6 x 30-second Wingate protocols toward fewer and shorter sprint protocols?

Summary

This current-opinion review argues that classic sprint interval training using four to six 30-second all-out Wingate sprints is not clearly justified as optimal, is demanding, and may be less time-efficient than claimed. The authors recommend more research on fewer and shorter sprints, especially reduced-exertion HIIT protocols using brief 20-second sprints.

Methodology

  • No primary sample; narrative review of SIT and REHIT literature.
  • Primarily cycle sprinting.
  • Work intervals: 20-30 seconds.
  • Recovery: Varied; classic protocols often 4 minutes.
  • Intensity: All-out or supramaximal.
  • About 10-30 minutes.
  • Often 3 times/week in cited studies.
  • Varied.
  • Current opinion narrative review
  • VO2max, Insulin sensitivity, and Tolerability were tracked.

Outcomes

VO2max

Shorter/fewer sprint protocols often improved VO2max in cited studies.

Narrative examples included about 7%-19% increases.

Improved

Insulin sensitivity

REHIT glucose and insulin-sensitivity results were inconsistent.

Mixed

Tolerability

Classic SIT is fatiguing; shorter REHIT may be more tolerable.

Mixed

Insights

  • Classic 4-6 x 30-second Wingate SIT should not be treated as the only evidence-based sprint format.
  • Very short protocols may be more practical when the goal is user adherence and low time burden.

Limitations

  • Narrative current-opinion article, not a systematic review.
  • Safety and adherence conclusions are based on limited data.
  • Many cited studies were small and heterogeneous.

Safety

  • No primary adverse-event dataset was collected in this article.
  • The authors reported no adverse events during one 8-week REHIT intervention in 16 overweight/obese prehypertensive type 2 diabetes patients, but explicitly cautioned that this does not prove safety.
  • The review discusses concerns that classic SIT may be unsafe, impractical, or intolerable, but states that evidence for poor medium- or long-term adherence is lacking.