Objectives: To compare the magnitudes of change in heart rate, systolic blood pressure (SBP), diastolic blood pressure (DBP), mean blood pressure, and rate-pressure product (RPP) during 3 abdominal exercises: straight partial sit-up (SPSU), oblique partial sit-up (OPSU), and the AbSculptor(R) sit-up; and to examine the effect of breath holding on these parameters.
Design: Prospective, repeated measures.
Setting: Autonomic research laboratory in a major medical center.
Participants: Fourteen normal male and female volunteers (age range, 24-37y; mean, 30.4y).
Interventions: Hemodynamic parameters were recorded during each abdominal exercise performed with and without breath holding. Mean peak values were calculated for 1 minute before exercise, during exercise, and for 10 minutes after exercise.
Main outcome measures: Statistical analysis examined for differences in the hemodynamic changes among the 3 exercises under both conditions (with and without breath holding).
Results: Heart rate, SBP, DBP, mean blood pressure, and RPP increased during all 3 exercises. The mean peak heart rate and RPP increases were greater for the OPSU than the AbSculptor (heart-rate increase, 21.1+/-6.6bpm vs 17.6+/-5.7bpm, P=.03; RPP increase, 36.9+/-15.5bpm.mmHg vs 29.4+/-10.1bpm.mmHg, P=.05). For all 3 exercises, breath holding significantly increased the hemodynamic parameter elevations during exercise, with the exception of heart rate (SBP, P<.001; DBP, P<.001; mean blood pressure, P<.001; RPP, P=.02). Quantitatively, breath holding during the OPSU resulted in the largest exercise-associated increases in heart rate (21.0+/-8.1bpm), mean blood pressure (22.2+/-16.4mmHg), and RPP (44.9+/-22.3bpm.mmHg). Postexercise, all hemodynamic parameters generally returned to baseline within several minutes.
Conclusion: When performing the OPSU, SPSU, or the AbSculptor exercises as used in this investigation, normal individuals exercising at low intensities may experience peak heart rate and mean blood pressure increases of 30bpm and 50mmHg, respectively. Voluntary breath holding significantly increased the peak blood pressure elevations and RPP for all 3 exercises, but particularly for the OPSU.