Acute exercise improves glucose effectiveness but not insulin sensitivity in paraplegia

Abstract

Purpose: To determine the effect of a single session of arm crank ergometry (ACE) exercise on carbohydrate metabolism immediately and 24 h after the exercise bout in paraplegia and able-bodied controls (ABC).

Methods: Paraplegia (n = 11; 91% male; age 34.8 ± 11.4 years) and ABC (n = 6; 67% male; age 28.7 ± 11.9 years) underwent 45 min of ACE exercise at 75% VO_2Peak. Glucose effectiveness (Sg) and insulin sensitivity (Si) were assessed. Data were analyzed with two-way mixed analysis of variance and Wilcoxon rank-sum or signed-rank post hoc test.

Results: VO_2Peak was lower in paraplegia versus ABC (22.3 ± 3.99 vs. 30.8 ± 2.9 ml/kg/min, p = 0.003). Si was lower paraplegia vs. ABC immediately following exercise (3.28 ± 1.6 vs. 5.30 ± 1.2 min^-1/[µU/mL^-1]x10^-4, p = 0.023). In paraplegia, Sg was higher immediately after exercise than baseline (B: 0.021 ± 0.01 vs. I: 0.026 ± 0.01 min^-1, p = 0.037). Twenty-four hours after exercise, Sg was lower than immediately following exercise (I: 0.026 ± 0.01 vs. 24: 0.017 ± 0.01 min^-1, p = 0.001), but not different than baseline in paraplegia (B: 0.021 ± 0.01 vs. 24: 0.017 ± 0.01 min^-1, p = 0.216). In the ABC group, Sg was not different at all timepoints (p > 0.05). Si did not differ at all timepoints (p > 0.05).

Conclusion: A single bout of ACE at 75% VO_2Peak helped to acutely control glucose metabolism in those with paraplegia by increasing Sg by nearly 27%; however, this was not sustained past 24-hours. These data provide support for regular exercise engagement.Implications for RehabilitationDisorders of glucose metabolism have been reported at a greater prevalence in persons with spinal cord injury.A single bout of arm crank ergometry exercise at 75% VO_2Peak helped to acutely control glucose metabolism persons with paraplegia; however, this was not sustained past 24 h.These data provide support for regular exercise engagement in persons with paraplegia.

Keywords: Spinal cord injury; exercise; glucose effectiveness; glucose metabolism; insulin sensitivity; paraplegia.