High intensity and sprint interval training, and work-related cognitive function in adults: A systematic review.

Objectives: To assess evidence on the impact of acute and chronic high intensity interval training (HIIT) and sprint interval training (SIT) on work-related performance tests of cognitive function in adults.

Methods: The databases PubMed, CINAHL, Scopus, PsycINFO, Embase, and the Cochrane Library were searched for relevant articles up to August 2022. Eligible studies assessed the effects of HIIT (70%-100% VO ) and/or SIT (≥100% VO ) on cognitive function test scores in cognitively healthy adults, relative to a control or comparative exercise group/condition. Data on participant characteristics, exercise protocol, key outcomes, and intervention setting were extracted. Study quality was assessed using a 9 (single session HIIT/SIT) and 14 (multiple session HIIT/SIT) item checklist.

Results: Thirty-six studies (15 countries; n = 11-945 participants) met inclusion criteria. Mean quality scores were "fair-to-good" for acute (single session; mean = 6.9 [SD 1.0]) and chronic (multiple session; mean = 9.8 [SD 1.6]) training studies. Eighteen from 36 studies (12/20 [55%] acute and 6/16 [38%] chronic training studies) evidenced significant improvements in aspects of cognitive function related to work performance (i.e., attention, inhibition, memory, information processing speed, cognitive flexibility, intelligence, reaction time, and learning). Only four studies tested the impact of HIIT/SIT on cognitive function in a work-based setting (e.g., the office or home).

Conclusions: While there is promising evidence, particularly from acute training studies, to indicate that high intensity, short duration exercise benefits cognitive function in adults, there is very limited evidence of application in workplace contexts. To better understand the potential benefits to employee performance and safety, HIIT/SIT and cognitive function research needs to transition from laboratory to "in-situ" occupational settings.