The impact of high‐intensity interval training on the cTnT response to acute exercise in sedentary obese young women

Aims This study characterized (a) the cardiac troponin T (cTnT) response to three forms of acute high‐intensity interval exercise (HIE), and (b) the impact of 12 weeks of HIE training on the cTnT response to acute exercise in sedentary obese young women. Methods Thirty‐six sedentary women were randomized to traditional HIE training (repeated 4‐minute cycling at 90% O 2max interspersed with 3‐minute rest, 200 kJ/session), work‐equivalent sprint interval exercise (SIE) training (repeated 1‐minute cycling at 120% O 2max interspersed with 1.5‐minute rest) or repeated‐sprint exercise (RSE) training (40 × 6‐second all‐out sprints interspersed with 9‐second rest) group. cTnT was assessed using a high‐sensitivity assay before and immediately, 3 and 4 hours after the 1st (PRE), 6th (EARLY), 20th (MID), and 44th (END) training session, respectively. Results cTnT was elevated ( P < 0.05) after all forms of acute interval exercise at the PRE and EARLY assessment with cTnT response higher ( P < 0.05) after HIE (307%) and SIE (318%) than RSE (142%) at the PRE assessment. All forms of acute interval exercise at MID and END had no effect on the cohort cTnT concentration post‐exercise (all P > 0.05). Conclusion For sedentary obese young women, both HIE and SIE, matched for total work, induced a similar elevation in cTnT after acute exercise with a smaller rise observed after RSE. By the 44th training session, almost no post‐exercise cTnT elevation was observed in all three groups. Such information is relevant for clinicians as it could improve medical decisionmaking.