Effects of 4 weeks of low intensity hand grip isometric training with vascular occlusion in older adults

Introduction: By the middle of this century, the number of people of age 65 and over will more than double to 80 million (US census bureau, 1993). As more and more older people are getting added to the population, it becomes vital to understand the mechanisms and processes which can play a crucial role in their overall well being. The goal of the present study was to study the benefits of a novel method of training which can be an alternative to high intensity training and also be equally beneficial without the risks of heavy training in older adults. It was hypothesized that low intensity hand grip isometric training with vascular occlusion leads to increased peak forearm blood flow (FBF) and forearm vascular conductance (FVC) as compared to high intensity training in older adults. Methods: Older participants (60 years or more) were recruited from the Ames community (Training group, n=9; control group, n=10). They were non smokers, did not participate in any structured hand grip exercise and did not have any diagnosed cardiovascular disease, PVD or diabetes. Intervention group did low intensity hand grip isometric exercise with vascular occlusion [20% Maximum voluntary contraction (MVC), 130% resting SBP] while the control group did high intensity isometric exercise (75% MVC) for 4 weeks. Resting FBF, peak FBF, resting FVC and peak FVC were calculated before and after the training in each group. Results: No statistically significant changes were seen in either FBF or FVC in any of the groups. Also, strength and size changes did not reach significance. Conclusion: Previous literature convincingly proves that conventional resistance training leads to strength and size gains. However, there were no changes in either group in the current study. The study also had a few limitations. The 4 weeks study period might not have been long enough to evoke a convincing and significant outcome. Some gender based differences in FBF response were seen as well. Further research is warranted before any conclusions can be drawn regarding the applicability of low intensity exercise with vascular occlusion