title: Creatine co-ingestion with carbohydrate or cinnamon extract provides no added benefit to anaerobic performance.
abstract: The insulin response following carbohydrate ingestion enhances creatine transport into muscle. Cinnamon extract is promoted to have insulin-like effects, therefore this study examined if creatine co-ingestion with carbohydrates or cinnamon extract improved anaerobic capacity, muscular strength, and muscular endurance. Active young males (n = 25; 23.7 ± 2.5 y) were stratified into 3 groups: (1) creatine only (CRE); (2) creatine+ 70 g carbohydrate (CHO); or (3) creatine+ 500 mg cinnamon extract (CIN), based on anaerobic capacity (peak power·kg(-1)) and muscular strength at baseline. Three weeks of supplementation consisted of a 5 d loading phase (20 g/d) and a 16 d maintenance phase (5 g/d). Pre- and post-supplementation measures included a 30-s Wingate and a 30-s maximal running test (on a self-propelled treadmill) for anaerobic capacity. Muscular strength was measured as the one-repetition maximum 1-RM for chest, back, quadriceps, hamstrings, and leg press. Additional sets of the number of repetitions performed at 60% 1-RM until fatigue measured muscular endurance. All three groups significantly improved Wingate relative peak power (CRE: 15.4% P = .004; CHO: 14.6% P = .004; CIN: 15.7%, P = .003), and muscular strength for chest (CRE: 6.6% P < .001; CHO: 6.7% P < .001; CIN: 6.4% P < .001), back (CRE: 5.8% P < .001; CHO: 6.4% P < .001; CIN: 8.1% P < .001), and leg press (CRE: 11.7% P = .013; CHO: 10.0% P = .007; CIN: 17.3% P < .001). Only the CRE (10.4%, P = .021) and CIN (15.5%, P < .001) group improved total muscular endurance. No differences existed between groups post-supplementation. These findings demonstrate that three different methods of creatine ingestion lead to similar changes in anaerobic power, strength, and endurance.
authors: a Department of Kinesiology and Physical Education, Faculty of Science , Wilfrid Laurier University , Waterloo , Ontario , Canada N2L 3C5.
authors: Hashim
authors: H
authors: Islam
authors: b Department of Kinesiology and Physical Education, Faculty of Arts and Science , University of Lethbridge , Lethbridge , Alberta , Canada T1K 3M4.
authors: Nick J
authors: NJ
authors: Yorgason
authors: a Department of Kinesiology and Physical Education, Faculty of Science , Wilfrid Laurier University , Waterloo , Ontario , Canada N2L 3C5.
authors: Tom J
authors: TJ
authors: Hazell
mesh_terms: D000328:Adult; D015308:Anaerobic Threshold / Q000187:drug effects*; D002935:Cinnamomum zeylanicum / Q000737:chemistry*; D003401:Creatine / Q000008:administration & dosage / Q000494:pharmacology*; D006801:Humans; D008297:Male; D053580:Muscle Strength / Q000187:drug effects; D058573:Performance-Enhancing Substances / Q000008:administration & dosage / Q000494:pharmacology*; D010807:Physical Endurance / Q000187:drug effects; D010936:Plant Extracts / Q000008:administration & dosage / Q000494:pharmacology*; D055815:Young Adult
chemical_list: D058573:Performance-Enhancing Substances; D010936:Plant Extracts; D003401:Creatine
keywords: Ergogenic aids; Wingate test; anaerobic power; creatine supplementation; maximal strength