Observing the Relationship Between Additional Measures of Handgrip Strength and the 6-Minute Push Test in Ambulatory Young Adults.

Manual wheelchair users have been shown to have low functional capacity and limited ability to perform activities of daily living. Conventional protocols for assessing physical attributes such as muscle function in this population have unique boundaries such as expensive testing equipment and procedures not specific to wheelchair propulsion. The measurement of muscle function using electronic handgrip dynamometry has shown promise in assessing additional characteristics beyond strength capacity alone. This study aimed to determine the correlations of electronic handgrip dynamometry derived strength, time to peak force generation, fatigability (22.40±10.12%), isometric control, and asymmetry with aerobic capacity in ambulatory young adults. We included 34 recreationally active ambulatory adults aged 23.76±3.57 years. Muscle function was assessed using electronic handgrip dynamometry. Aerobic capacity was examined using the six-minute wheelchair push test (1112.17±92.84ft). Fatigability (22.40±10.12%) showed a significant, near moderate negative correlation (r=-0.345, p<0.05) with push test outcomes, while the correlation with all other measures was not-significant. Our findings show that electronic handgrip dynamometry derived fatigability is related to aerobic capacity in those who use manual wheelchairs. Given the relationships shown in the current study, electronic handgrip dynamometry has promise for assessing functional health in persons with disabilities, which has particular relevance for SCI, and could be used in clinical practice and physical medicine and rehabilitation (PM&R) as a tool to examine functional capacity in applicable populations. However, future research is warranted to assess the concurrent validity of the additional measures of handgrip strength assessing muscle function.