Comparing Isometric Exercise Protocols Using A Novel Exercise Ball Versus A Traditional Computerized Dynamometer

Abstract

Hypertension is the leading risk factor for death and disability worldwide. Isometric handgrip (IHG) training is endorsed as one of the “Best Proven Nonpharmacological Interventions for Prevention and Treatment of Hypertension” by the American Heart Association/American College of Cardiology in their current guidelines. Barriers such as cost of the handgrip devices and tedium arising from repeating the same exercises, pose a challenge for widespread implementation of IHG training. Therefore, alternative devices that provide potential for a wide variety of isometric exercises warrant further investigation. PURPOSE: To determine whether an acute bout of IHG exercise, performed with a novel exercise ball (NEB), elicits similar cardiovascular responses and ratings of perceived exertion (RPE) to a traditional IHG device (TID). METHODS: Ten healthy adults (age: 24±7 yrs; ♀= 7; systolic blood pressure (BP)/diastolic BP: 99/56±9/6 mmHg) randomly performed two different IHG exercise protocols, one with the NEB, and the other with the TID. Both protocols involved 4, 2-min isometric contractions with 1-min rest periods between contractions, but NEB employed hand and adductor isometric contractions at 20-30% of maximum voluntary contraction (MVC), while the TID protocol involved alternating handgrip contractions performed at 30% of MVC. Heart rate (HR) and BP were recorded pre-, mid-, and post-exercise bout, as well as every 5-min during seated rest. RPE was assessed using the Borg CR-10 scale, following each contraction. The two protocol bouts were separated by 30-min of seated rest. RESULTS: The NEB and TID protocols elicited similar HR and systolic BP responses (p>0.05). However, the TID protocol elicited a greater diastolic BP response (12±1 mmHg) than the NEB protocol (8±1 mmHg; p=0.026). Additionally, a higher RPE was observed for TID, compared to NEB (p<0.001). CONCLUSION: This preliminary data suggests that the NEB protocol elicits similar cardiovascular responses (HR and systolic BP) while being perceived to require less effort, compared to the TID. Such an isometric exercise ball offers the potential for a wide variety of isometric exercises to be performed during training. Supported by University of Windsor Research Stimulus Fund Grant 813306