Abstract

OBJECTIVE:

To examine effects of protein-carbohydrate intake on ambulation performance in persons with incomplete spinal cord injury (SCI).

DESIGN:

Double-blinded treatment with washout and placebo crossover.

SETTING:

Academic medical center.

PARTICIPANTS:

Three subjects aged 34 to 43 years with incomplete SCI at C5-T4.

INTERVENTIONS:

Subjects walked to fatigue on 5 consecutive days. On fatigue, participants consumed 48g of vanilla-flavored whey and 1g/kg of body weight of carbohydrate (CH(2)O). Weekend rest followed, and the process was repeated. A 2-week washout was interposed and the process repeated using 48g of vanilla-flavored soy.

MAIN OUTCOME MEASURES:

Oxygen consumed (Vo(2); in L/min), carbon dioxide evolved (Vco(2)), respiratory exchange ratio (RER: Vco(2)/Vo(2)), time (in minutes), and distance walked (in meters) were recorded. Caloric expenditure was computed as Vo(2) by time by 21kJ/L (5kcal/L) of oxygen consumed. Data were averaged across the final 2 ambulation sessions for each testing condition.

RESULTS:

Despite slow ambulation velocities (range, .11-.34m/s), RERs near or above unity reflected reliance on CH(2)O fuel substrates. Average ambulation time to fatigue was 17.8% longer; distance walked 37.9% longer, and energy expenditure 12.2% greater with the whey and CH(2)O supplement than with the soy drink.

CONCLUSIONS:

Whey and CH(2)O ingestion after fatiguing ambulation enhanced ensuing ambulation by increasing ambulation distance, time, and caloric expenditure in persons with incomplete SCI.