Darren Burke

McMaster University | McMaster · Department of Kinesiology

The purpose was to determine if creatine supplementation, consumed immediately before and immediately after exercise, with different dosing frequency (i.e., 2 or 3 d wk) could enhance the gains in muscle size and strength from resistance training (RT) in young adults. A group of 38 physically active, nonresistance trained university students (21-28...

Muscle and strength loss will occur during periods of physical inactivity and immobilization. Creatine supplementation may have a favorable effect on muscle mass and strength independently of exercise. The purpose of this study was to determine the effects of creatine supplementation on upper limb muscle mass and muscle performance after immobiliza...

The purpose of this study was to compare changes in muscle insulin-like growth factor-I (IGF-I) content resulting from resistance-exercise training (RET) and creatine supplementation (CR). Male (n=24) and female (n=18) participants with minimal resistance-exercise-training experience (=1 year) who were participating in at least 30 min of structured...

Position Statement The following seven points related to the intake of protein for healthy, exercising individuals constitute the position stand of the Society. They have been approved by the Research Committee of the Society. 1) Vast research supports the contention that individuals engaged in regular exercise training require more dietary protein...

Changes in muscle mass and strength will vary, depending on the volume and frequency of training. The purpose of this study was to determine the effect of short-term equal-volume resistance training with different workout frequency on lean tissue mass and muscle strength. Twenty-nine untrained volunteers (27-58 years; 23 women, 6 men) were assigned...

The purpose was to compare changes in lean tissue mass, strength, and myofibrillar protein catabolism resulting from combining whey protein or soy protein with resistance training. Twenty-seven untrained healthy subjects (18 female, 9 male) age 18 to 35 y were randomly assigned (double blind) to supplement with whey protein (W; 1.2 g/kg body mass w...

Creatine monohydrate supplementation is beneficial for enhancing high-intensity exercise performance, especially activities that involve repeated sprints. Creatine monohydrate supplementation is common in ice-hockey players. The purpose of this study was to determine the effect of creatine monohydrate supplementation on sprint skating performance i...

Creatine, which is increasingly being used as an oral supplement, is naturally present in the body. Studies on the fate of a particular dose of creatine require that the creatine be labeled, and for studies in humans the use of a stable isotopic label is desirable. The concentrations of total creatine and total creatinine were determined using HPLC...

Our purpose was to determine the effects of creatine supplementation combined with resistance training on bone mineral content and density in older men. Twenty-nine older men (age 71 y) were randomized (double blind) to receive creatine (0.3 g/kg creatine for 5 d and 0.07 g/kg thereafter) or placebo while participating in resistance training (12 we...

The purpose of this study was to examine the effect of a 5-day creatine (CR) supplementation period on red blood cell (RBC) CR uptake in vegetarian and nonvegetarian young women. Blood samples were collected from lacto-ovo vegetarians (VG, n = 6, age 21.8 +/- 1.9 yrs) and nonvegetarians (NV, n = 6, age 21.7 +/- 1.9 yrs) before and after a 5-day CR...

Mitochondrial dysfunction occurs early in the course of ALS, and the mitochondria may be an important site for therapeutic intervention. Creatine stabilizes the mitochondrial transition pore, and is important in mitochondrial ATP production. In a transgenic mouse model of ALS, administration of creatine prolongs survival and preserves motor functio...

The authors previously found that creatine (Cr) combined with 12 weeks of resistance training enhanced muscle strength and endurance and lean tissue mass (LTM) in older men. Their purpose in this study was to assess these variables with cessation of Cr combined with 12 weeks of reduced training (33% lower volume) in a subgroup of these men (n = 8,...

To compare the change in muscle creatine, fiber morphology, body composition, hydration status, and exercise performance between vegetarians and nonvegetarians with 8 wk of creatine supplementation and resistance training. Eighteen VG and 24 NV subjects (19-55 yr) were randomly assigned (double blind) to four groups: VG + creatine (VGCr, N=10), VG...

Alpha-lipoic acid has been found to enhance glucose uptake into skeletal muscle in animal models. Studies have also found that the co-ingestion of carbohydrate along with creatine increases muscle creatine uptake by a process related to insulin-stimulated glucose disposal. The purpose of this study was to determine the effect of alpha-lipoic acid o...

Johnston, APW, Burke, DG, MacNeil, LG, and Candow, DG. Effect of creatine supplementation during cast-induced immo-bilization on the preservation of muscle mass, strength, and endurance. J Strength Cond Res 23(1): 116–120, 2009—Mus-cle and strength loss will occur during periods of physical inactivity and immobilization. Creatine supplementation ma...

A reagent-free Partial Least Squares (PLS)-based analysis of creatine in urine using UV absorption spectroscopy is described. Creatine and creatinine standards were used to demonstrate the feasibility of the method, giving plots of predicted versus actual values which had R 2 values of 0.999. Fifty-six individual urine samples, some collected over...

To study the effect of creatine (Cr) supplementation combined with resistance training on muscular performance and body composition in older men. Thirty men were randomized to receive creatine supplementation (CRE, N = 16, age = 70.4 +/- 1.6 yr) or placebo (PLA, N = 14, age = 71.1 +/- 1.8 yr), using a double blind procedure. Cr supplementation cons...

The purpose of this study was to assess the effect of oral glutamine supplementation combined with resistance training in young adults. A group of 31 subjects, aged 18-24 years, were randomly allocated to groups (double blind) to receive either glutamine (0.9 g x kg lean tissue mass(-1) x day(-1); n = 17) or a placebo (0.9 g maltodextrin x kg lean...

Our purpose was to assess muscular adaptations during 6 weeks of resistance training in 36 males randomly assigned to supplementation with whey protein (W; 1.2 g/kg/day), whey protein and creatine monohydrate (WC; 0.1 g/kg/day), or placebo (P; 1.2 g/kg/day maltodextrin). Measures included lean tissue mass by dual energy x-ray absorptiometry, bench...

Purpose: To study the effect of creatine (Cr) supplementation combined with resistance training on muscular performance and body composition in older men. Methods: Thirty men were randomized to receive creatine supplementation (CRE, N = 16, age = 70.4 +/- 1.6 yr) or placebo (PLA, N = 14, age = 71.1 +/- 1.8 yr), using a double blind procedure. Cr...

OBJECTIVE: To compare the changes in hamstring length resulting from modified proprioceptive neuromuscular facilitation flexibility training in combination with cold-water immersion, hot-water immersion, and stretching alone. DESIGN AND SETTING: Training-only subjects stood motionless for 10 minutes, while subjects in the cold group stood in a cold...

Since the discovery that oral ingestion of creatine leads to an increase in intramuscular creatine, its supplementation has become widespread. However, the dosage necessary to maximize retention and create significant increases in intramuscular creatine is poorly understood. In this study, 24-hour urinary creatine and creatinine levels of 20 univer...

Athletic performance, injury prevention, and rehabilitation are areas that have been positively influenced through the intervention of flexibility training programs. The literature already acknowledges that benefits realized through proprioceptive neuromuscular facilitation-type stretching are superior to other methods. Despite the widespread use o...

Dietary supplementation (SUP) has become a significant part of athletic training. Studies indicate that creatine (Cr) can enhance short-duration, high-intensity activities. This study examined the effect of 21 days of low dose Cr SUP ( approximately 7.7 g/day) and resistance training on force output, power output, duration of mean peak power output...

The purpose of this study was to compare dynamic pushup (DPU) and plyometric push-up (PPU) training programs on 2 criterion measures: (a) the distance achieved on a sitting, 2-handed medicine ball put, and (b) the maximum weight for 1 repetition of a sitting, 2-handed chest press. Thirty-five healthy women completed 18 training sessions over a 6-we...

The purpose of this study was to compare 2 methods of delivering the same proprioceptive neuromuscular facilitation (PNF) flexibility exercise protocol: one manual and the other machine. Thirty-six college students (18 male and 18 female), between 18 and 25 years of age, were randomly assigned to 1 of 3 groups: manual, machine, or control. The manu...

The purpose of this study was to compare the changes in force production resulting from isometric strength training, in combination with 3 different treatment conditions: control, cold water immersion, and hot water immersion. Forty-five noninjured subjects between the ages of 18 and 25 were randomly assigned to 1 of 3 groups: control, cold, or hot...

Creatine is found in the urine of subjects ingesting creatine monohydrate as an ergogenic aid. Creatinine, the catabolic breakdown product of creatine, is a major constituent of normal urine. It is of interest to follow the excretion of creatine and creatinine in urine as a function of time after creatine ingestion. In this study, creatine and crea...

Traditionally, near maximal isometric efforts have been used to elicit the beneficial facilitations and inhibitions associated with strength and flexibility improvements using proprio-ceptive neuromuscular facilitation (PNF) and modified PNF techniques. Although concentric reversal of antagonists has been used clinically, there is little evidence r...

To present several modifications of the standard sit-and-reach protocol. Many exercises designed to increase strength and aerobic capacity tend to decrease the flexibility of the erector spinae and hamstrings musculature. Less-than-ideal flexibility in these soft tissues may increase the risk of injury during training, competition, or activities of...