Name: LETICIA NASCIMENTO SANTOS NEVES
Publication date: 30/10/2023
Examining board:
Name |
Role |
|---|---|
| LUCIANA CARLETTI | Advisor |
Summary: Introduction: A novel proposal of High-Intensity Interval Training (HIIT) with elastic
resistance (EL-HIIT) has been under investigation. EL-HIIT is easy to apply and accessible;
however, its efficacy and safety in terms of acute responses still need to be studied. Objective:
To compare the cardiopulmonary and blood pressure responses after a single session of two
types of high-intensity interval training (EL-HIIT vs. HIIT on the treadmill) in healthy young
individuals. Methods: Twenty-two participants underwent two incremental tests, the
Cardiopulmonary Exercise Test (CPET) and the Elastic Cardiopulmonary Exercise Test
(ECPET), with a one-week interval between them. Subsequently, they performed a session of
HIIT on the treadmill (10 x 1:1 min at 85-90% V O2max from CPET), and after a one-week
interval, a session of EL-HIIT (10 x 1:1 min at 85-90% V O2max). The Student's t-test was used
to compare peak and mean values of the HIIT and EL-HIIT sessions. ANOVA and Mixed-
Effects Model of Repeated Measures (Bonferroni/Tukey post-hoc) were used to compare HIIT,
EL-HIIT, and control (for heart rate variability - HRV and blood pressure - BP). Cohen's d
effect size was used to compare the sessions. To assess inter and intra-individual BP, MDD
(minimum detectable difference), ICC (intra-class correlation coefficient), CV (coefficient of
variation), SEM (standard error of measurement), and ET (typical error) were used. Results: In
the EL-HIIT session, heart rate (HR), ventilation (V E), oxygen consumption (V O2), carbon
dioxide production (V CO2), and RPE were higher than in the HIIT session (P < 0.05).
Comparing HIIT and EL-HIIT, no differences were found when analyzing each interval during
the session. In recovery, there was a decrease in systolic blood pressure (SBP) for both EL-
HIIT and HIIT, but of greater magnitude in EL-HIIT, as calculated by MDD, at 50, 70, and 80
minutes post-exertion compared to control (P < 0.05). The intra-individual analyses of systolic
and diastolic blood pressure showed ICC of 0.92 and 0.88, CV of 6.0 and 9.5%, and MDD of
4.1 and 4.3, respectively. EL-HIIT presented higher sympathetic autonomic variables (stress
index, SNS index) compared to HIIT/control and lower parasympathetic autonomic variables
(RMSSD, pNN50, PNS index) compared to HIIT/control after exertion (P < 0.05). Conclusion:
A single session of EL-HIIT promoted a greater magnitude of post-exercise hypotension
compared to HIIT. EL-HIIT presented higher autonomic stress in recovery compared to HIIT
without changes in nitrite/nitrate concentrations.
