title: Effect of short-term creatine supplementation on markers of skeletal muscle damage after strenuous contractile activity.
abstract: The protective effect of short-term creatine supplementation (CrS) upon markers of strenuous contractile activity-induced damage in human and rat skeletal muscles was investigated. Eight Ironman triathletes were randomized into the placebo (Pl; n = 4) and creatine-supplemented (CrS; n = 4) groups. Five days prior to the Ironman competition, the CrS group received creatine monohydrate (20 g day(-1)) plus maltodextrin (50 g) divided in two equal doses. The Pl group received maltodextrin (50 g day(-1)) only. The effect of CrS (5 g day(-1)/kg body weight for 5 days) was also evaluated in a protocol of strenuous contractile activity induced by electrical stimulation in rats. Blood samples were collected before and 36 and 60 h after the competition and were used to determine plasma activities of creatine kinase (CK), lactate dehydrogenase (LDH), aldolase (ALD), glutamic oxaloacetic acid transaminase (GOT), glutamic pyruvic acid transaminase (GPT), and C-reactive protein (CRP) level. In rats, plasma activities of CK and LDH, muscle vascular permeability (MVP) using Evans blue dye, muscle force and fatigue were evaluated. Activities of CK, ALD, LDH, GOT, GTP, and levels of CRP were increased in the Pl group after the competition as compared to basal values. CrS decreased plasma activities of CK, LDH, and ALD, and prevented the rise of GOT and GPT plasma activities. In rats, CrS delayed the fatigue, preserved the force, and prevented the rise of LDH and CK plasma activities and MVP in the gastrocnemius muscle. CrS presented a protective effect on muscle injury induced by strenuous contractile activities.
authors: Departamento de Fisiologia e Biofísica, Instituto de Ciências Biomédicas I, Universidade de São Paulo, Av. Lineu Prestes, 1524, Sala 105, Butantan, São Paulo, SP, 05508-900, Brazil. tubaraousp@sti.com.br
authors: Reinaldo Abunasser
authors: RA
authors: Bassit
authors: Carlos Hermano da Justa
authors: CH
authors: Pinheiro
authors: Kaio Fernando
authors: KF
authors: Vitzel
authors: Antônio José
authors: AJ
authors: Sproesser
authors: Leonardo R
authors: LR
authors: Silveira
authors: Rui
authors: R
authors: Curi
mesh_terms: D000328:Adult; D000818:Animals; D015415:Biomarkers / Q000032:analysis / Q000378:metabolism*; D003401:Creatine / Q000008:administration & dosage*; D019587:Dietary Supplements; D004334:Drug Administration Schedule; D004353:Drug Evaluation, Preclinical; D004558:Electric Stimulation / Q000009:adverse effects; D006801:Humans; D008297:Male; D009043:Motor Activity / Q000187:drug effects / Q000502:physiology; D009119:Muscle Contraction / Q000187:drug effects* / Q000502:physiology; D018763:Muscle Fatigue / Q000187:drug effects / Q000502:physiology; D018482:Muscle, Skeletal / Q000187:drug effects* / Q000293:injuries / Q000378:metabolism / Q000473:pathology; D009135:Muscular Diseases / Q000378:metabolism / Q000517:prevention & control; D005082:Physical Exertion / Q000187:drug effects / Q000502:physiology*; D010919:Placebos; D051381:Rats; D017208:Rats, Wistar; D013997:Time Factors
chemical_list: D015415:Biomarkers; D010919:Placebos; D003401:Creatine