Quantification of an Exercise Rehabilitation Program for Severely Burned Children: The Standard of Care at Shriners Hospitals for Children®-Galveston

Abstract

Currently, there are no clear guidelines for the implementation of rehabilitative exercise training (RET) in burned individuals. Therefore, we quantified the training logs for exercise intensity, frequency, and duration of 6 weeks of this program to develop a basic framework for outpatient RET in patients recovering from severe burns. Thirty-three children (11 female, [mean ± SD] 12 ± 3 years, 145 ± 18 cm, 40 ± 11 kg, 49 ± 31 BMI percentile) with severe burns (49 ± 15% total body surface area burned, with 35 ± 22% third-degree burns) completed our 6-week resistance and aerobic exercise training program. Cardiorespiratory fitness (peak VO2), strength, power, and lean body mass (LBM) were measured before and after RET. Outcome measures were analyzed as a relative percentage of values in age- and sex-matched nonburned children (11 female, 12 ± 3 years, 154 ± 20 cm, 49 ± 22 kg, 56 ± 25 BMI percentile). At discharge, burned children had lower LBM (77% of age-sex-matched nonburn values), peak torque (53%), power (62%), and cardiorespiratory fitness (56%). After 6 weeks of training, LBM increased by 5% (82% of nonburn values), peak torque by 18% (71%), power by 20% (81%), and cardiorespiratory fitness by 18% (74%; P < .0001 for all). Quantification of data in exercise training logs suggested that physical capacity can be improved by aerobic exercise training performed at five metabolic equivalents (>70% of peak VO2) at least 3 days/week and 150 minutes/week and by resistance training performed at volume loads (reps × sets × weight) of 131 kg for the upper body and 275 kg for the lower body for 2 days/week. We present for the first time the quantification of our RET and provide clear exercise prescription guidelines specific to children with severe burn injury.

Figure 1.

Effect of rehabilitative exercise training on lean body mass (LBM) (A), strength (peak torque, B; mean power, C), and cardiorespiratory fitness (peak VO₂, D) in burned children. All values are expressed relative to age- and sex-matched nonburn values and are reported as mean ± 95% CI.

Figure 2.

Effect of rehabilitative exercise training on absolute strength (peak torque, A; mean power, C) and lean body mass (LBM)-normalized strength (B, D) in burned children. Healthy age- and sex-matched nonburned controls are shown for reference. All values are reported as mean ± 95% CI. ***P < .001; ****P < .0001.

Figure 3.

Effect of rehabilitative exercise training on peak cardiorespiratory fitness and indices of cardiovascular function. Absolute peak values are shown for VO₂ (A), work rate (B), and heart rate (C). Indices of peak cardiovascular function are stroke volume (D), oxygen delivery (E), cardiac muscle efficiency (F), and pulmonary dead space (G). Healthy age- and sex-matched nonburned controls are shown for reference. All values are reported as mean ± 95% CI. *P < .05; **P < .01; ***P < .001; ****P < .0001.

Figure 4.

Submaximal to maximal changes in oxygen uptake (VO₂) and heart rate during the modified Bruce exercise stress test for burned children at discharge (pretraining) and after 6 weeks of rehabilitative exercise training (post-training). All values are reported as mean ± 95% CI. *P < .05 and ****P < .0001 indicate differences from pre- to post-training.

Figure 5.

Comparison of relative peak oxygen uptake (% peak VO₂, A) and relative peak heart rate (% peak HR, B) at the indicated exercise work rate between burned children and healthy age- and sex-matched nonburned children. All values are reported as mean ± 95% CI.

Figure 6.

Comparison of the relative relationship between percent peak oxygen uptake (VO₂) and percent peak heart rate between burned children and healthy age- and sex-matched nonburned children.