Effects of prandial challenge on triglyceridemia, glycemia, and pro-inflammatory activity in persons with chronic paraplegia.

CONTEXT/OBJECTIVE: Exaggerated postprandial lipemia has been reported after spinal cord injury (SCI). We examined metabolite and accompanying pro-inflammatory biomarker responses to repeat feeding of typical high-fat meals in individuals with chronic paraplegia. DESIGN: Descriptive trial. METHODS: Metabolites (triglycerides, glucose, and insulin) and inflammatory biomarkers (interleukin-6 and high-sensitivity C-reactive protein (hsCRP)) were measured under fasting conditions in 11 recreationally active individuals with chronic (>1 year) paraplegia. Subjects received high-fat meals at time point 0 and again at minute 240. Antecubital venous blood was obtained at time points -30 (fasting), 0 (first meal), 30, 60, 90, 120, 240 (second meal), 360, and 480 minutes. Correlations were examined among the study variables. Exploratory subgroup analysis was performed for subjects with levels of postprandial glucose greater than >200 mg/dl. RESULTS: Triglycerides showed a significant rise 4 hours after eating. Basal inflammatory markers were elevated, and did not undergo additional change during the testing. Additionally, subjects with excessive postprandial glucose responses showed higher hsCRP levels than those having typical glucose responses both for fasting (11.8 ± 6.5 vs. 2.9 ± 2.7 mg/l, P = 0.064) and postprandial (11.1 ± 4.9 vs. 3.7 ± 3.8 mg/l, P = 0.018) values. CONCLUSIONS: Despite elevations in metabolic response markers, inflammatory markers did not change significantly after consumption of population-representative (i.e. hypercaloric) mixed-nutrient meals. Levels of fasting CRP in the high-risk range are consistent with other reports in persons with SCI and continue to pose concern for their cardiovascular disease risk. The possible association between postprandial metabolic responses and inflammatory states warrants further investigation to identify individual component risks for this secondary health hazard.

Metabolic responses to 4 different body weight-supported locomotor training approaches in persons with incomplete spinal cord injury.

OBJECTIVE: To describe metabolic responses accompanying 4 different locomotor training (LT) approaches. DESIGN: Single-blind, randomized controlled trial. SETTING: Rehabilitation research laboratory, academic medical center. PARTICIPANTS: Individuals (N=62) with minimal walking function due to chronic motor-incomplete spinal cord injury. INTERVENTION: Participants trained 5 days/week for 12 weeks. Groups were treadmill-based LT with manual assistance (TM), transcutaneous electrical stimulation (TS), and a driven gait orthosis (DGO) and overground (OG) LT with electrical stimulation. MAIN OUTCOME MEASURES: Oxygen uptake (V˙o2), walking velocity and economy, and substrate utilization during subject-selected "slow," "moderate," and "maximal" walking speeds. RESULTS: V˙o2 did not increase from pretraining to posttraining for DGO (.00 ± .18L/min, P=.923). Increases in the other groups depended on walking speed, ranging from .01 ± .18 m/s (P=.860) for TM (slow speed) to .20 ± .29 m/s (P=.017) for TS (maximal speed). All groups increased velocity but to varying degrees (DGO, .01 ± .18 Ln[m/s], P=.829; TM, .07 ± .29 Ln[m/s], P=.371; TS, .33 ± .45 Ln[m/s], P=.013; OG, .52 ±.61 Ln[m/s], P=.007). Changes in walking economy were marginal for DGO and TM (.01 ± .20 Ln[L/m], P=.926, and .00 ± .42 Ln[L/m], P=.981) but significant for TS and OG (.26 ± .33 Ln[L/m], P=.014, and .44 ± .62 Ln[L/m], P=.025). Many participants reached respiratory exchange ratios ≥ 1 at any speed, rendering it impossible to statistically discern differences in substrate utilization. However, after training, fewer participants reached this ceiling for each speed (slow: 9 vs 6, n=32; moderate: 12 vs 8, n=29; and maximal 15 vs 13, n=28). CONCLUSIONS: DGO and TM walking training was less effective in increasing V˙o2 and velocity across participant-selected walking speeds, while TS and OG training was more effective in improving these parameters and also walking economy. Therefore, the latter 2 approaches hold greater promise for improving clinically relevant outcomes such as enhanced endurance, functionality, or in-home/community ambulation.

Nutrient intake and body habitus after spinal cord injury: an analysis by sex and level of injury.

BACKGROUND/OBJECTIVES: To examine nutrient intake and body mass index (BMI) in the spinal cord injury (SCI) population according to level of injury and sex. DESIGN: Cross-sectional study conducted at 2 SCI treatment centers. PARTICIPANTS/METHODS: Seventy-three community-dwelling individuals with C5-T12 ASIA Impairment Scale (AIS) A or B SCI. Subjects were divided into 4 groups: male tetraplegia (N = 24), male paraplegia (N = 37), female tetraplegia (N =1), and female paraplegia (N = 11). Mean age was 38 years; 84% were male; 34% were white, 41% were African American, and 25% were Hispanic. Participants completed a 4-day food log examining habitual diet. Dietary composition was analyzed using Food Processor II v 7.6 software. RESULTS: Excluding the 1 woman with tetraplegia, total calorie intake for the other 3 groups was below observed values for the general population. The female paraplegia group tended to have a lower total calorie intake than the other groups, although macronutrient intake was within the recommended range. The male tetraplegia group, male paraplegia group, and the 1 woman with tetraplegia all had higher than recommended fat intake. Intake of several vitamins, minerals, and macronutrients did not meet recommended levels or were excessively low, whereas sodium and alcohol intake were elevated. Using adjusted BMI tables, 74.0% of individuals with SCI were overweight or obese. CONCLUSIONS: Women with paraplegia tended to maintain healthier diets, reflected by lower caloric and fat intakes, fewer key nutrients falling outside recommended guidelines, and less overweight or obesity. Individuals with tetraplegia tended to take in more calories and had higher BMIs, and using adjusted BMI, the majority of the population was overweight or obese. The majority of people with SCI would benefit from nutritional counseling to prevent emerging secondary conditions as the population with SCI ages.

Circuit training and protein supplementation in persons with chronic tetraplegia.

UNLABELLED: Circuit resistance training (CRT) performed three times weekly for 40-45 min each session increases muscular strength and both aerobic and anaerobic capacity in untrained individuals with chronic paraplegia. Whether similar CRT is also effective for conditioning of persons with chronic tetraplegia is unknown. In addition, protein supplementation (PS) before and immediately postexercise has been shown to enhance exercise adaptations. PURPOSE: This study aimed to investigate whether a modified 40-45 min CRT program will improve fitness attributes in individuals with tetraplegia and whether these changes are enhanced by PS. METHODS: Eleven individuals with chronic tetraplegia underwent 6 months of CRT performed three times per week. Six randomly assigned participants received PS (whey protein = 36-37 g) in split doses immediately before and after exercise sessions. Others consumed a matched protein dose 24 h postexercise. Measurements of one-repetition maximum (1-RM) strength for six different resistance exercises, arm peak oxygen consumption (VO2peak), and arm anaerobic power (Wingate) were obtained 3 months before (-3mo), at the beginning (0mo), 3 months into (3mo), and 6 months after (6mo) the beginning of CRT. RESULTS: One-repetition maximum increased by 8%-11% ± 6%-12% for each successive 3-month period (P ≤ 0.001-0.012), independent of PS group (P = 0.105). VO2peak increased significantly from 0mo to 6mo with immediate PS (35% ± 29%, P = 0.020) but failed to reach significance for delayed PS (15% ± 8%, P = 0.147). Power drop changes during the Wingate test were also only significant for the immediate PS (median difference 40W, P = 0.028) and not for delayed (10W, P = 0.500). CONCLUSION: CRT effectively increased muscular strength, aerobic capacity, and anaerobic fatigue resistance in persons with chronic tetraplegia. The latter two conditioning benefits were further enhanced by timely PS.

Nutrient supplementation post ambulation in persons with incomplete spinal cord injuries: a randomized, double-blinded, placebo-controlled case series.

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.