Optimizing sprint interval exercise for post‐exercise hypotension: A randomized crossover trial

Abstract

This study aimed to examine the effects of manipulating the rest intervals during sprint interval training (SIT) on post-exercise hypotension and within-session oxygen consumption.Thirty healthy, trained adults (aged 30.9 ± 8.7 years; 14 males, 16 females; BMI 22.1 ± 2.3 kg/m 2 ; VO 2 max 50.7 ± 7.8 ml/kg/min) completed two different SIT protocols (4x 30-seconds all-out cycling sprints) with a one-week washout period. Sprint bouts were separated by either 1 (R1) or 3 (R3) minutes of active recovery. Both before and throughout the 45 min after the training, peripheral systolic (pSBP) and diastolic (pDBP) blood pressure, central systolic (cSBP) and diastolic (cDBP) blood pressure, aortic pulse wave velocity (aPWV), stroke volume (SV), and heart rate (HR) were assessed. Throughout the SIT protocols, oxygen consumption (VO 2 ) was monitored.There were no significant differences in time spent at 75%, 85%, 95%, and 100% of maximal VO 2 between R1 and R3. After R3, there was a significant reduction in pSBP, pDBP, cSBP, cDBP, and aPWV. After R1, there were no changes in the respective parameters. There were significant interaction effects in pSBD (p < 0.001), pDBP (p < 0.001), cSBP (p < 0.001), cDBP (p = 0.001), and aPWV (p = 0.033). HR significantly increased after both conditions. Only R1 resulted in a significant reduction in SV.Longer resting intervals during SIT bouts seem to result in more substantial post-exercise hypotension effects. Time spent at a high percentage of maximal VO 2 was not affected by rest interval manipulation. KEYWORDSSprint interval training; postexercise hypotension; blood pressure; hemodynamics; rest interval manipulation Highlights-Previous studies assessing the health and performance effects of sprint interval training mainly follow very uniform protocols. Little attention has been given to assessing whether training variables can be modulated to achieve beneficial cardiometabolic adaptations.-3-minute resting intervals during sprint interval training bouts result in more substantial post-exercise hypotension effects compared to 1-minute resting intervals. Time spent at a high percentage of maximal oxygen consumption was not affected.-The presented findings have important implications for cardiovascular prevention programs as modified sprint interval training protocols potently stimulate post-exercise hypotension in a time-efficient manner.

Similar Postexercise Hypotension After MICT, HIIT, and SIT Exercises in Middle-Age Adults

“…It is important to highlight that the exercise sessions were able to blunt the increase in BP seen during the no-exercise CTRL session. Across all exercise protocols, the PEH responses we measured were similar to the respective literature in normotensive participants for MICT (5,10–12,14–16,19), HIIT (8,12,13,26,43), and SIT exercise (10,12,28–31). If these acute reductions were repeated with chronic training they may contribute to chronic reductions in BP that could be clinically significant as reductions as small as 2 mm Hg SBP can reduce stroke mortality by 10% and ischemic heart disease mortality by 7% (44).…”

Comparing Post-Exercise Hypotension after Different Sprint Interval Training Protocols in a Matched Sample of Younger and Older Adults

“…Interestingly, no PEH effect could be detected after SIT1 in either of the groups. As stated earlier, this is in line with previous research [ 17 , 20 ] and may be attributed to a higher total exercise volume [ 23 ] or higher exercise intensities [ 20 ] in SIT3, compared to SIT1. Furthermore, it could be debated that the longer rest periods during SIT3 resulted in a stronger reduction in stroke volume between the exercise bouts, consequently leading to higher fluctuations in the cardiac output and thus the greater blood flow variations leading to the more pronounced NO release [ 16 ].…”

“…The reduction in the peripheral blood pressure after SIT3 is in line with previous studies assessing the acute responses to different SIT protocols consisting of four to six bouts of 30 s all-out sprints interspersed by 4–4.5 min of rest [ 13 , 14 , 16 ]. Only very few studies addressed the PEH effect after the SIT protocols with shorter rest intervals (32–60 s), reporting inconsistent results [ 17 , 20 ].…”

“…Although the literature addressing PEH in SIT is still sparse, previous studies have shown that SIT can induce a similar PEH effect as HIIT, despite a shorter exercise time [ 13 , 14 ]. However, other studies report conflicting results [ 15 , 16 , 17 ]. The contradicting results may be explained by the inconsistent exercise protocols applied.…”

“…Surprisingly, few efforts have been made to identify the optimal SIT protocol design [ 18 ]. Initial studies show that manipulating training variables, such as the number of sprint bouts [ 18 ] or the sprint-to-rest ratio [ 17 , 19 , 20 ], affects the magnitude of PEH after SIT. Therefore, further research comparing the different SIT protocols is highly warranted to detect the most effective protocols to induce PEH.…”