Effects of Impact Versus Non-impact Cardiovascular Machines in Individuals between Age 50 and 80 Years

Older adults are at increased risk of injury when initiating exercise due to inactivity, functional limitation, illness, or fall risk. We studied a novel non-impact cardio unit in an effort to determine whether there were differences in physiologic, functional, and strength benefits compared to a treadmill (TM), while producing less stress on the knee and lessening the risk of fall and injury. Utilizing a prospective, randomized, non-blinded, cohort design, individuals aged 50–80 years were recruited and enrolled in a 16-week exercise program. Subjects were randomly allocated to either exercise on the Cybex arc trainer or on a TM. Participants exercised for 120 min per week. Resistance was adjusted to achieve a target RPE in each group. Functional, strength, and physiologic markers were analyzed through balance testing, ten – repetition max leg press, body composition analysis, and lipid panel results. Overall health-related quality of life was also measured. There was a significant improvement in triglyceride and very low density lipoprotein levels from baseline to exit within the arc trainer group. An equal and significant increase in strength capacity was observed in both the arc trainer and TM groups, as were feelings of increased energy, improved emotional well-being, and decreased fatigue. Leg strength increased, percentage of body fat decreased, and balance improved following use of either an arc trainer or a TM in a study population of 58 participants over a 16-week period. This study demonstrated that positive change occurs, physiologically and psychologically when an arc trainer or TM is utilized. Given the similar benefits seen in this study, use of a non-impact modality such as the arc trainer may be a better alternative in the older population.