Resistance exercise can modify cardiovascular responses of professors during teaching and sleep

Abstract

Background: Both work activity and reduced nocturnal decrease in blood pressure (BP) are related to higher cardiovascular risk. Objectives: The aim of the present study was to assess the blood pressure and autonomic responses of university professors during teaching and sleeping periods after different resistance exercise (RE) intensities. Methods: Ten normotensive professors (33.6 ± 3.4 years, 82.4 ± 12.4 kg; 177.0 ± 7.5 cm; 26.2 ± 3.2 kg/m2) randomly underwent control (CONT) and RE before initiating their daily activities. RE consisted of a circuit training lasting 40 minutes at 40% and 80% of one repetition maximum test (40% 1RM and 80% 1RM). Systolic BP (SBP) and diastolic BP (DBP) as well as heart rate variability indicators in the time (RRi) and frequency domains (LF, HF, LF:HF ratio) were evaluated while resting and 24 hours after the sessions. The average day-period (DP), night-period (NP) and nocturnal BP fall (%NBPF) of SBP and DBP were calculated. Results: During teaching, SBP (CONT: ∆ = 8.1 ± 9.1 mmHg; 40% 1RM: ∆ = 10.8 ± 10.5 mmHg and 80% 1RM: ∆ = 10.3 ± 7.9 mmHg; P < 0.01) and DBP increased (CONT: ∆ = 8.0 ± 9.9 mmHg; P < 0.05). In sleep, SBP (CONT: ∆ =-14.8 ± 5.9 mmHg and 40% 1RM: ∆ =-13.1 ± 6.0 mmHg; P < 0.001) and DBP decreased (40% 1RM: ∆ =-12.9 ± 6.2 mmHg and 80% 1RM: ∆ =-12.3 ± 3.6 mmHg; P < 0.001), RRi and HF increased (P < 0.01) and LF and LF:HF ratio decreased (P < 0.01) after CONT, 40% 1RM and 80% 1RM, while the class period did not change in different sessions (P > 0.05). DBP showed different results to 40% 1RM (NT: 58.8 ± 5.1 mmHg and %NBPF:-24.2 ± 3.4 %; P < 0.05) when compared with CONT (NT: 61.9 ± 5.2 mmHg and %NBPF:-18.2 ± 4.5%; P < 0.05) and 80% 1RM (NT: 63.2 ± 5.9 mmHg and %NBPF:-18.1 ± 4.9%). Conclusions: RE at 40% 1RM and 80% 1RM attenuated DBP values of subsequent teaching, however only 40% 1RM promoted better NT-BP and %NBPF values in university professors.