To compare the cardiorespiratory response to a graded aerobic exercise challenge between adolescents with symptomatic sport-related concussion
(SSRC) and healthy control subjects.
A quasi-experimental non-randomized study at a multi-disciplinary pediatric concussion program was conducted. Thirty-four adolescents with SSRC (19 males and 15 females) and 40 healthy control subjects (13 males and 27 females) completed Buffalo Concussion Treadmill testing (BCTT) until either symptom exacerbation or volitional fatigue. Main outcome measures included heart rate (HR), oxygen consumption (V˙O2
), carbon dioxide production (V˙CO2
), and minute ventilation (V˙E
) at rest and at test termination, and change from rest in variables (ΔHR, ΔV˙O2
, and ΔV˙E
) during the first 5 stages of the BCTT. Main outcomes were analyzed using three-way mixed model ANOVAs, with group status (control vs. SSRC) and sex (male vs. female) as between-subjects factors, and time (BCTT stage) as the within-subjects factor.
No group differences in resting HR, systolic and diastolic blood pressure (BP), ΔV˙O2
, and V˙E
were observed. During the first 5 stages of the BCTT, no group differences in ΔV˙O2
, and V˙E
were observed, however SSRC patients demonstrated higher ratings of perceived exertion (p
< .0005) compared to control subjects. No sex-based differences were observed among SSRC patients on measures collected at rest and during early stages of BCTT.
Although SSRC patients exhibited higher ratings of perceived exertion during a graded aerobic exercise challenge, no differences in cardiorespiratory response were observed compared to control subjects exercising at equivalent workloads. Further work is needed to elucidate the physiological mechanisms underlying exercise intolerance