One HICA dose was 583 mg as sodium salt (corresponding 500 mg of HICA) mixed with juice or water. One

PLACEBO dose included 650 mg maltodextrin mixed also with juice or water. Both powders were scaled and packed ready for the subjects in 1.5 ml Eppendorf tubes. The supplements were advised to ingest three times per day in equal time intervals with meals. Training Training consisted of 5-7 training sessions per week including 3-4 soccer sessions, 1-2 resistance exercise sessions, and one match. Resistance exercise session included both maximal strength and speed-strength exercises. All subjects were advised to keep training diaries on which they marked all training exercises as well as subjective evaluation of training alertness JPH203 mw and the morning onset of delayed muscle soreness (DOMS) in lower and upper extremities. In both assessments the scale was from 1 to 5 where 5 is the best training alertness and the strongest soreness in the muscles. It has been shown earlier that a correlation coefficient between repeated measurements of muscle soreness is good (r = 0.96; [26]). Each subject was individually supervised how to keep training diaries and to report DOMS. Nutrition Before the beginning of the study, each subject was supervised to continue his normal sport nutrition program. On the testing day the subjects were supervised not to use any sport or dietary

supplements. They were BIRB 796 price supervised also to keep food diaries for five days in the 4-week period for what unless they were provided with specific verbal and written instructions and procedures for reporting detailed dietary intake, including how to record portions by using household measures, exact brand names and preparation techniques. Dietary intake of the subjects was registered for five days including Saturday and Sunday. The food diaries were analyzed using the Micro Nutrica nutrient-analysis software (version 3.11, Social Insurance Institution of Finland). Data collection and analysis Each subject was tested before and after the 4-week (28 days)

loading period at the same time of day (Figure 1). Figure 1 Test protocol before and after the 4-week loading period. D = DXA, RB = rest blood sample, W = standard warm up, 5J = standing 5-jump, CMJ = counter movement jump, 20 m = 20 m sprint, B = blood sample, 400 m = 400 m run, BM = bench 1RM, BE = bench strength endurance, SM = squat 1RM, SE = squat strength endurance. Blood sampling In the morning blood samples were taken from an antecubital vein in the sitting position. Two milliliters blood from a vein was taken in K2 EDTA tubes (Terumo Medical Co., Leuven, Belgium) for measurements of hemoglobin and hematocrit concentration with a Sysmex KX 21N Analyzer (Sysmex Co., Kobe, Japan). The intra-assay coefficient of variation (CV) was 1.5% for hemoglobin and 2.0% for hematocrit.