Lower extremity general muscle moment patterns in healthy individuals during recumbent cycling

OBJECTIVE

The purpose of this study was to compare lower extremity generalized muscle moments across two workloads during recumbent bicycling in younger and older healthy adults.

DESIGN

The study design was a comparative investigation of cycling patterns.

BACKGROUND

Biomechanical data regarding muscle activation, kinematic, and kinetic patterns have been presented for upright cycling, but only a few studies have evaluated biomechanical patterns during the alternative configuration of recumbent cycling.

METHODS

Twenty-four healthy adults, classified by age into two different groups, under 35 and over 50 years of age, rode a recumbent bicycle at a constant cadence (60-65 rpm) and at two different resistances (0.5 and 1.0 kg m) while kinematic and kinetic data were recorded. General muscle moments were calculated using joint kinematic and kinetic data via inverse dynamic equations.

RESULTS

The ankle general muscle moment remained plantar flexor throughout the pedaling cycle; the knee general muscle moment remained flexor throughout the cycle, except during the power phase of the higher workload where an extensor general muscle moment was observed; and the hip general muscle moment was extensor with a transient flexor general muscle moment period during the recovery phase. Increased workload led to increases in ankle plantar flexor and knee extensor general muscle moment magnitudes, but no changes at the hip. Age had no effect on general muscle moment magnitudes or patterns.

CONCLUSIONS

Configurational differences between the upright and recumbent bicycle do not affect patterns, but the total output requirements do affect the magnitudes of the general muscle moments.

RELEVANCE

Based on previous studies, the recumbent bicycle appears to be a safe rehabilitation tool for post-cerebrovascular accident and cardiorespiratory patients, but in order to more properly and efficiently use the recumbent bicycle as a rehabilitation tool, normative biomechanical data are necessary. The current study is the first such investigation to report normative data of lower extremity general muscle moment patterns during recumbent cycling. Effects of age and workload were also demonstrated.

Comparison of cycling kinetics during recumbent bicycling in subjects with and without diabetes

We compared recumbent bicycle kinetics in diabetic peripheral neuropathy and nondiabetic men (nine per group). 3D kinematic and force pedal data in a linked-segment model were used. The generalized muscle moment (GMM) patterns were similar between the two groups except for (1) decreased maximum knee flexor moment, (2) increased minimum knee flexor GMM, and (3) maximum hip extensor GMM by the diabetic subjects. Similar to the walking support moment, a summation moment immutable pattern was observed, although the groups accomplished it differently. The diabetic group utilized the hip during the power phase and the knee during the recovery phase. The nondiabetic group utilized both joints together during both phases. Differences in ankle GMM were not observed, suggesting further research using the recumbent bicycle as an exercise modality for diabetic peripheral neuropathy patients to enhance ankle range of motion and strength, commonly observed walking deficits.