Improving Power Output in Older Adults Using Plyometrics in a Body Mass–Supported Treadmill

Abstract

Dobbs, TJ, Simonson, SR, and Conger, SA. Improving power output in older adults using plyometrics in a body mass-supported treadmill. J Strength Cond Res 32(9): 2458-2465, 2018-The purpose of this study was to determine if performing plyometrics in a body mass-supported treadmill would lead to greater increases in power output and functional strength in older adults compared with traditional strength training. Twenty-three participants were randomized to strength (SG, n = 8), plyometric (PG, n = 8), or control (CG, n = 7) groups. The SG and PG exercised 3 times per week for 8 weeks, whereas the CG performed no exercise. Timed sit-to-stand and stair climb, estimated maximal muscular isotonic strength, and isokinetic strength were assessed pre- and posttraining. Significant improvements occurred in the PG vs. CG in the timed chair sit-to-stand (22.11 ± 8.48%; p = 0.013), timed stair climb (14.68 ± 6.28%; p = 0.002), and stair climb power (16.59 ± 9.07%; p < 0.001). PG and SG significantly increased their estimated 1 repetition maximum in the leg extension and single leg lunge (p < 0.05), and PG was significantly more powerful at all 3 velocities in both flexion and extension compared with SG and CG ranging from 24.54 to 61.85% (p < 0.001) except for 60°·s extension during isokinetic testing. Eight weeks of plyometrics in a body mass-supported treadmill can significantly improve functional strength and power in older adults. In this study, the PG increased muscular strength at the same rate or better than the SG without performing any resistance training. The PG also outperformed SG during the functional tests. These results suggest that plyometrics, if modified and performed in a safe environment, can increase muscular strength and power and improve functional abilities in older adults.

Assisted Jumping in Healthy Older Adults: Optimizing High-Velocity Training Prescription

“…Comparatively, 1 previous study using BW supported jumping on a treadmill reported that older adults reached a much greater RPE of 7–8 of 10, which can possibly be attributed to a greater training volume, increased perceived difficulty to during single-limb movements, or both (13). Therefore, the setup used in this study was perceived to be easier not only compared with BW jumping, which has also been shown in younger individuals (36), but also compared with data from 1 of the only other studies to investigate assisted jump training in older adults (13). Therefore, if exercise enjoyment plays a role in exercise adherence, reducing BW by 30% may be ideal in older populations.…”

“…Although young healthy athletes may be able to quickly produce enough force to reap the benefits of overspeed training, it is possible that older adults may not be able to generate a sufficient level of force as quickly, meaning that the optimal assistance levels for older adults may differ than those of young healthy populations (23,35). One previous study has shown that assisted jumping is likely beneficial for increasing the power output of older adults but that study neither measured training velocities and forces nor determined the optimal assistance level for training (13). Rather, the study design included a continuous increase in training load overtime.…”

Long-Term Side Effects of Breast Cancer on Force Production Parameters

“…However, the subjects in their study could have been influenced by the short-term side effects of surgery, radiotherapy, and chemotherapy, which may have a greater impact compared with long-term side effects on strength parameters. On the other hand, the authors used isokinetic measurement at 180°·s −1 , an angular velocity used for power analysis, which is related to fast twitch fiber activation (7), whereas we used isometric contractions to calculate the RFI.…”