TY - JOUR
T1 - Aerobic conditioning
T2 - An effective therapy in McArdle's disease
AU - Haller, Ronald G.
AU - Wyrick, Phil
AU - Taivassalo, Tanja
AU - Vissing, John
PY - 2006/6
Y1 - 2006/6
N2 - Objective: Susceptibility to exertional cramps and rhabdomyolysis in myophosphorylase deficiency (McArdle's disease [MD]) may lead patients to shun exercise. However, physical inactivity may worsen exercise intolerance by further reducing the limited oxidative capacity caused by blocked glycogenolysis. We investigated whether aerobic conditioning can safely improve exercise capacity in MD. Methods: Eight MD patients (4 men and 4 women; age range, 33-61 years) pedaled a cycle ergometer for 30 to 40 minutes a day, 4 days a week, for 14 weeks, at an intensity corresponding to 60 to 70% of maximal heart rate. We monitored serum creatine kinase levels; changes in peak cycle work, oxygen uptake, and cardiac output; presence and magnitude of a spontaneous and glucose-induced second wind; and citrate synthase and β-hydroxyacyl coenzyme A dehydrogenase enzyme activities in quadriceps muscle. Results: The prescribed exercise program increased average work capacity (36%), oxygen uptake (14%), cardiac output (15%), and citrate synthase and β-hydroxyacyl coenzyme A dehydrogenase enzyme levels (80 and 62%, respectively) without causing pain or cramping or increasing serum creatine kinase. A spontaneous and glucose-induced second wind was present and was of similar magnitude in each patient before and after training. Interpretation: Moderate aerobic exercise is an effective means of improving exercise capacity in MD by increasing circulatory delivery and mitochondrial metabolism of bloodborne fuels.
AB - Objective: Susceptibility to exertional cramps and rhabdomyolysis in myophosphorylase deficiency (McArdle's disease [MD]) may lead patients to shun exercise. However, physical inactivity may worsen exercise intolerance by further reducing the limited oxidative capacity caused by blocked glycogenolysis. We investigated whether aerobic conditioning can safely improve exercise capacity in MD. Methods: Eight MD patients (4 men and 4 women; age range, 33-61 years) pedaled a cycle ergometer for 30 to 40 minutes a day, 4 days a week, for 14 weeks, at an intensity corresponding to 60 to 70% of maximal heart rate. We monitored serum creatine kinase levels; changes in peak cycle work, oxygen uptake, and cardiac output; presence and magnitude of a spontaneous and glucose-induced second wind; and citrate synthase and β-hydroxyacyl coenzyme A dehydrogenase enzyme activities in quadriceps muscle. Results: The prescribed exercise program increased average work capacity (36%), oxygen uptake (14%), cardiac output (15%), and citrate synthase and β-hydroxyacyl coenzyme A dehydrogenase enzyme levels (80 and 62%, respectively) without causing pain or cramping or increasing serum creatine kinase. A spontaneous and glucose-induced second wind was present and was of similar magnitude in each patient before and after training. Interpretation: Moderate aerobic exercise is an effective means of improving exercise capacity in MD by increasing circulatory delivery and mitochondrial metabolism of bloodborne fuels.
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U2 - 10.1002/ana.20881
DO - 10.1002/ana.20881
M3 - Article
C2 - 16718692
AN - SCOPUS:33744797628
SN - 0364-5134
VL - 59
SP - 922
EP - 928
JO - Annals of Neurology
JF - Annals of Neurology
IS - 6
ER -