Contributions
Abstract: P1640
Type: LB Poster
Abstract Category: Late Breaking News
Background: Asymmetry (bilateral differences) in leg power, strength, peak oxygen uptake (VO2) and bone mineral density have been reported in individuals with multiple sclerosis (MS). Due to the unpredictable asymmetrical nature of MS, further investigation is warranted.
Purpose: A pilot study was completed to assess whether individuals with MS exhibited asymmetry in VO2 onset kinetics during single leg cycling.
Methods: Five volunteers (3 women, 2 men; Age: 43.2±7.3 yrs, Height: 170.5±7.4 cm, Weight: 90.2±18.5 kg) with relapsing-remitting MS and an Expanded Disability Status Score less than 6.5 completed 4-6 bouts of constant-load cycling at 80% of the limb specific ventilatory threshold (VT) in each limb for evaluation of VO2 onset kinetics. Each participant"s limbs were stratified as stronger (S) or weaker (W) based on self-report and confirmed using peak power output in watts achieved during a ramped single leg max cycling test.
Results: The workload corresponding to 80% VT was not different between limbs (S: 59.0±10.9 vs. W: 57.4±9.3 watts, p=0.20). However the time constant of the VO2 onset kinetics (S: 42.7±14.0 vs. W: 32.14±11.08 seconds, p=0.009) and mean response times (S: 58.2±12.2 vs. W: 52.3±16.5 seconds, p=0.03) were both significantly slower in the S compared to the W leg. No significant differences in oxygen deficit and oxygen cost (P>0.05) were noted.
Conclusion: This preliminary data suggests that asymmetries in VO2 kinetics exist in MS patients in a counter-intuitive way, i.e. better VO2 kinetics for the “weaker” limb. Future work will need to focus on the underlying mechanisms eliciting these differences in VO2 kinetics between limbs.
Disclosure: Rebecca D. Larson: nothing to disclose
John W. Farrell III: nothing to disclose
Gregory S. Cantrell: nothing to disclose
David J. Lantis: nothing to disclose
Brian A. Pribble: nothing to disclose
Daniel J. Larson: nothing to disclose
Carl Ade: nothing to disclose
Abstract: P1640
Type: LB Poster
Abstract Category: Late Breaking News
Background: Asymmetry (bilateral differences) in leg power, strength, peak oxygen uptake (VO2) and bone mineral density have been reported in individuals with multiple sclerosis (MS). Due to the unpredictable asymmetrical nature of MS, further investigation is warranted.
Purpose: A pilot study was completed to assess whether individuals with MS exhibited asymmetry in VO2 onset kinetics during single leg cycling.
Methods: Five volunteers (3 women, 2 men; Age: 43.2±7.3 yrs, Height: 170.5±7.4 cm, Weight: 90.2±18.5 kg) with relapsing-remitting MS and an Expanded Disability Status Score less than 6.5 completed 4-6 bouts of constant-load cycling at 80% of the limb specific ventilatory threshold (VT) in each limb for evaluation of VO2 onset kinetics. Each participant"s limbs were stratified as stronger (S) or weaker (W) based on self-report and confirmed using peak power output in watts achieved during a ramped single leg max cycling test.
Results: The workload corresponding to 80% VT was not different between limbs (S: 59.0±10.9 vs. W: 57.4±9.3 watts, p=0.20). However the time constant of the VO2 onset kinetics (S: 42.7±14.0 vs. W: 32.14±11.08 seconds, p=0.009) and mean response times (S: 58.2±12.2 vs. W: 52.3±16.5 seconds, p=0.03) were both significantly slower in the S compared to the W leg. No significant differences in oxygen deficit and oxygen cost (P>0.05) were noted.
Conclusion: This preliminary data suggests that asymmetries in VO2 kinetics exist in MS patients in a counter-intuitive way, i.e. better VO2 kinetics for the “weaker” limb. Future work will need to focus on the underlying mechanisms eliciting these differences in VO2 kinetics between limbs.
Disclosure: Rebecca D. Larson: nothing to disclose
John W. Farrell III: nothing to disclose
Gregory S. Cantrell: nothing to disclose
David J. Lantis: nothing to disclose
Brian A. Pribble: nothing to disclose
Daniel J. Larson: nothing to disclose
Carl Ade: nothing to disclose