Exercise during gravity inversion: Acute and chronic effects

The purpose of this study was to determine whether gravity inversion could correctly be called an exercise, and whether inversion and inverted exercise produced safe blood pressure responses. Systolic blood pressure (SBP), diastolic blood pressure (DBP), heart rate (HR), and oxygen consumption (V̇O₂) were measured in 19 healthy young men (x̄ = 20.31 years) in seven positions: (1) standing passive (STD), (2) inverted passive (INV), (3) standing recovery postpassive inversion (SRPI), (4) standing exercise (SDE), (5) standing recovery poststanding exercise (SRPSE), (6) inverted exercise (INVE), and (7) inverted recovery postinverted exercise (IRPIE). Ten of the subjects participated in a five-week inversion training program, after which all 19 subjects were retested. Compared to STD, INV elicited significant increases in SBP/DBP and a significant decrease in HR. The average INV blood pressure was 146/97 mmHg, which was further increased during INVE to 158/101 mmHg. These responses increase the workload of the heart and may be dangerous to some populations. No physiologic adaptations occurred in any of the inverted positions as a result of inversion training. Gravity inversion should not be compared to or classified as an exercise. Some previously suggested inverted exercises are not recommended. Because of the nature of the responses, medical screening before the use of inversion devices is critical.