Effect of 12 months of creatine supplementation and whole-body resistance training on measures of bone, muscle and strength in older males.

BACKGROUND: The combination of creatine supplementation and resistance training (10-12 weeks) has been shown to increase bone mineral content and reduce a urinary indicator of bone resorption in older males compared with placebo. However, the longer-term effects (12 months) of creatine and resistance training on bone mineral density and bone geometric properties in older males is unknown. AIM: To assess the effects of 12 months of creatine supplementation and supervised, whole-body resistance training on bone mineral density, bone geometric properties, muscle accretion, and strength in older males. METHODS: Participants were randomized to supplement with creatine (n = 18, 49-69 years, 0.1 g·kg-1·d-1) or placebo (n = 20, 49-67 years, 0.1 g·kg-1·d-1) during 12 months of supervised, whole-body resistance training. RESULTS: After 12 months of training, both groups experienced similar changes in bone mineral density and geometry, bone speed of sound, lean tissue and fat mass, muscle thickness, and muscle strength. There was a trend (p = 0.061) for creatine to increase the section modulus of the narrow part of the femoral neck, an indicator of bone bending strength, compared with placebo. Adverse events did not differ between creatine and placebo. CONCLUSIONS: Twelve months of creatine supplementation and supervised, whole-body resistance training had no greater effect on measures of bone, muscle, or strength in older males compared with placebo.

Effect of pre-exercise and post-exercise creatine supplementation on bone mineral content and density in healthy aging adults.

Creatine supplementation, immediately before and immediately following resistance training, has been shown to increase muscle mass and strength. However, the effects of pre- exercise and post-exercise creatine supplementation on aging bone mineral content (BMC) and density (BMD) is unknown. Using a double-blind, repeated measures design, aging adults were randomized to one of three groups: creatine before (CR-B: n = 15; 53 ±â€¯3 years, 170.1 ±â€¯9.9 77.1 ±â€¯15.6 kg; 0.1 g·kg-1 creatine immediately before resistance training and 0.1 g·kg-1 cornstarch maltodextrin immediately after resistance training), creatine after (CR-A: n = 12; 55 ±â€¯4 years, 173.4 ±â€¯8.3 cm, 87.9 ±â€¯20.1 kg; 0.1 g·kg-1 cornstarch maltodextrin immediately before resistance training and 0.1 g·kg-1 of creatine immediately after resistance training), or placebo (PLA: n = 12; 57 ±â€¯7 years, 170.5 ±â€¯10.8 cm, 77.9 ±â€¯11.8 kg; 0.1 g·kg-1 cornstarch maltodextrin before and after resistance training). Whole-body resistance training was performed 3 days/week for 8 months. Prior to and following training and supplementation, BMC and BMD of the whole-body, limbs, femoral neck, lumbar spine, and total hip were determined by dual-energy X-ray absorptiometry. There was a time main effect (p = 0.037) for femoral neck BMD (CR-B; absolute change: -0.011 g/cm2, 95% CI [-0.028, 0.006], CR-A: absolute change: -0.014 g/cm2, 95% CI [-0.031, 0.003], PLA: absolute change: -0.006 g/cm2, 95% CI [-0.002, 0.010]), with no other differences. Creatine supplementation, independent of the timing of ingestion, has no effect on aging bone mineral content or density.

Strategic creatine supplementation and resistance training in healthy older adults.

Creatine supplementation in close proximity to resistance training may be an important strategy for increasing muscle mass and strength; however, it is unknown whether creatine supplementation before or after resistance training is more effective for aging adults. Using a double-blind, repeated measures design, older adults (50-71 years) were randomized to 1 of 3 groups: creatine before (CR-B: n = 15; creatine (0.1 g/kg) immediately before resistance training and placebo (0.1 g/kg cornstarch maltodextrin) immediately after resistance training), creatine after (CR-A: n = 12; placebo immediately before resistance training and creatine immediately after resistance training), or placebo (PLA: n = 12; placebo immediately before and immediately after resistance training) for 32 weeks. Prior to and following the study, body composition (lean tissue, fat mass; dual-energy X-ray absorptiometry) and muscle strength (1-repetition maximum leg press and chest press) were assessed. There was an increase over time for lean tissue mass and muscle strength and a decrease in fat mass (p < 0.05). CR-A resulted in greater improvements in lean tissue mass (Δ 3.0 ± 1.9 kg) compared with PLA (Δ 0.5 ± 2.1 kg; p < 0.025). Creatine supplementation, independent of the timing of ingestion, increased muscle strength more than placebo (leg press: CR-B, Δ 36.6 ± 26.6 kg; CR-A, Δ 40.8 ± 38.4 kg; PLA, Δ 5.6 ± 35.1 kg; chest press: CR-B, Δ 15.2 ± 13.0 kg; CR-A, Δ 15.7 ± 12.5 kg; PLA, Δ 1.9 ± 14.7 kg; p < 0.025). Compared with resistance training alone, creatine supplementation improves muscle strength, with greater gains in lean tissue mass resulting from post-exercise creatine supplementation.

Ingestion of low-dose ibuprofen following resistance exercise in postmenopausal women.

BACKGROUND: Postmenopausal women typically experience accelerated muscle loss which has a negative effect on strength. The maximum daily recommended dosage of ibuprofen (1,200 mg) following resistance exercise has been shown to increase muscle hypertrophy and strength in older adults. This study aimed to determine the effects of low-dose ibuprofen (400 mg) immediately following resistance exercise sessions on muscle mass and strength in postmenopausal women. METHODS: Participants were randomized to ingest ibuprofen (IBU: n = 15, 57.8 ± 5.1 years, 75.9 ± 9.0 kg, 165.9 ± 6.2 cm, BMI = 28 ± 4 kg/m(2)) or placebo (PLA: n = 13, 56.5 ± 4.4 years, 73.0 ± 10.4 kg, 163.1 ± 5.9 cm, BMI = 26 ± 9 kg/m(2)) immediately following resistance exercise (11 whole-body exercises), which was performed 3 days/week, on nonconsecutive days, for 9 weeks. Prior to and following training, measures were taken for lean tissue mass (dual-energy X-ray absorptiometry), muscle size of the elbow and knee flexors and extensors and ankle dorsiflexors and plantar flexors (ultrasound), and strength (one-repetition maximum leg press and chest press). RESULTS: Over the 9 weeks of training, there were significant changes (p < 0.05) in lean tissue mass (IBU, -1.1 ± 1.0 kg; PLA, -0.7 ± 1.4 kg), muscle size of the knee extensors (IBU, 0.3 ± 0.6 cm; PLA, 0.2 ± 0.7 cm), ankle dorsiflexors (IBU, 0.5 ± 0.8 cm; PLA, 0.1 ± 0.5 cm), and ankle plantar flexors (IBU, 0.3 ± 0.9 cm; PLA, 0.5 ± 0.9 cm), leg press strength (IBU, 20.6 ± 18.0 kg; PLA, 20.0 ± 20.0 kg), and chest press strength (IBU, 5.1 ± 9.5 kg; PLA, 8.1 ± 7.6 kg), with no differences between groups. CONCLUSION: Low-dose ibuprofen following resistance exercise has no greater effect on muscle mass or strength over exercise alone in postmenopausal women.

Using ballistocardiography to measure cardiac performance: a brief review of its history and future significance.

Ballistocardiography (BCG) is a non-invasive technology that has been used to record ultra-low-frequency vibrations of the heart allowing for the measurement of cardiac cycle events including timing and amplitudes of contraction. Recent developments in BCG have made this technology simple to use, as well as time- and cost-efficient in comparison with other more complicated and invasive techniques used to evaluate cardiac performance. Recent technological advances are considerably greater since the advent of microprocessors and laptop computers. Along with the history of BCG, this paper reviews the present and future potential benefits of using BCG to measure cardiac cycle events and its application to clinical and applied research.

Whey protein before and during resistance exercise has no effect on muscle mass and strength in untrained young adults.

PURPOSE: To determine the effects of whey protein before and during resistance exercise (RE) on body composition and strength in young adults. METHODS: Participants were randomized to ingest whey protein (PRO; 0.3 g/kg protein; n = 9, 24.58 ± 1.8 yr, 88.3 ± 17.1 kg, 172.5 ± 8.0 cm) or placebo (PLA; 0.2 g/kg cornstarch maltodextrin + 0.1 g/kg sucrose; n = 8, 23.6 ± 4.4 yr, 82.6 ± 16.1 kg, 169.4 ± 9.2 cm) during RE (3 sets of 6-10 repetitions for 9 whole-body exercises), which was performed 4 d/wk for 8 wk. PRO and PLA were mixed with water (600 ml); 50% of the solution containing 0.15 g/kg of PRO or PLA was consumed immediately before the start of exercise, and ~1.9% of the remaining solution containing ~0.006 g/kg of PRO or PLA was consumed immediately after each training set. Before and after the study, measures were taken for lean-tissue mass (dual-energy X-ray absorptiometry), muscle size of the elbow and knee flexors and extensors and ankle dorsiflexors and plantar flexors (ultrasound), and muscle strength (1-repetition-maximum chest press). RESULTS: There was a significant increase (p < .05) in muscle size of the knee extensors (PRO 0.6 ± 0.4 cm, PLA 0.1 ± 0.5 cm), knee flexors (PRO 0.4 ± 0.6 cm, PLA 0.5 ± 0.7 cm) and ankle plantar flexors (PRO 0.6 ± 0.7 cm, PLA 0.8 ± 1.4 cm) and chest-press strength (PRO 16.6 ± 11.1 kg, PLA 9.1 ± 14.6 kg) over time, with no differences between groups. CONCLUSION: The ingestion of whey protein immediately before the start of exercise and again after each training set has no effect on muscle mass and strength in untrained young adults.