Protein supplementation before and after resistance training in older men

Abstract

We determined the effects of protein supplementation immediately before (PRO-B) and after (PRO-A) resistance training (RT; 12 weeks) in older men (59-76 years), and whether this reduces deficits in muscle mass and strength compared to younger men (18-40 years). Older men were randomized to PRO-B (0.3 g/kg protein before RT + placebo after RT, n=9), PRO-A (placebo before + protein after RT, n=10), or PLA (placebo before and after RT, n=10). Lean tissue mass, muscle thickness of the elbow, knee, and ankle flexors and extensors, and leg and bench press strength were measured before and after RT and compared to databases of younger subjects (n=22-60). Myofibrillar protein degradation (3-methylhistidine) and bone resorption (cross-linked N-telopeptides) were also measured before and after RT. Lean tissue mass, muscle thickness (except ankle dorsi flexors), and strength increased with training (P<0.05), with little difference between groups. There were no changes in 3-methylhistidine or cross-linked N-telopeptides. Before RT, all measures were lower in the older compared to younger groups (P<0.05), except for elbow extensor muscle thickness. Following training, muscle thickness of the elbow flexors and ankle dorsi flexors and leg press strength were no longer different than the young, and elbow extensor muscle thickness was greater in the old men (P<0.05). Supplementation with protein before or after training has no effect on muscle mass and strength in older men. RT was sufficient to overcome deficits in muscle size of the elbow flexors and ankle dorsi flexors and leg press strength in older compared to younger men.

Methodological Issues Related to Thickness-Based Muscle Size Evaluation

“…Considering this fact, the above result brings up the question of the validity of using ultrasonic muscle thickness determined at rest to evaluate individual differences in muscle size. In previous studies, muscle thickness measurements with ultrasonography have been performed in standing (Abe et al, 1994;Akagi et al, 2010;Kubo et al, 2003aKubo et al, , 2003bMiyatani et al, 2003Miyatani et al, , 2004Pinkoski et al, 2006;Toji and Kaneko, 2007;Wakahara et al, 2010), supine (Ainscough-Potts et al, 2006;Arts et al, 2010;Campbell et al, 1995;Pillen et al, 2003Pillen et al, , 2007Reimers et al, 1998;Scholten et al, 2003), or prone (Candow and Chilibeck, 2005;Candow et al, 2006;Mohagheghi et al, 2007;Reimers et al, 1998) positions. In the standing position, the gravitational force acted on the muscles of interest in the proximal-distal direction.…”

Effects of a Nutritive Administration of Carbohydrates and Protein by Foodstuffs on Skeletal Muscle Inflammation and Damage After Acute Endurance Exercise

“…Therefore we measured creatine kinase in the serum as a parameter related to skeletal muscle damage and recovery [25]. Combinations of proteins/carbohydrates ingested before, after, or during endurance exercise have been our main physiological endpoint investigated in this study was skeletal muscle damage and recovery after exercise.…”

“…Combinations of proteins/carbohydrates ingested before, after, or during endurance exercise have been our main physiological endpoint investigated in this study was skeletal muscle damage and recovery after exercise. Therefore we measured creatine kinase in the serum as a parameter related to skeletal muscle damage and recovery [25]. Combinations of proteins/carbohydrates ingested before, after, or during endurance exercise have been shown to result in lowered post exercise muscle soreness [26] and lower plasma concentrations of both myoglobin [27] and CK [28].…”

Effects of protein supplementation combined with resistance exercise on body composition and physical function in older adults: a systematic review and meta-analysis

“…Of the 17 RCTs, 5 (19-21, 31, 32) had participants with a mean BMI .30.0, whereas the others had participants with a mean BMI of 25.0-29.9. Moreover, among the 17 RCTs, 8 had a sex-specific design for male participants (18,20,25,30,31,33,34,37), with an overall BMI Values are presented as means 6 SDs. 4 Value was estimated or calculated using statistical formulas with the data reported by the authors.…”

“…Six RCTs used a long intervention period of $24 wk, totaling 48-72 sessions (13,19,22,(24)(25)(26); 8 used a medium intervention period of $12 wk but ,24 wk, totaling 24-48 sessions (18,20,21,27,31,33,34,37); and 3 used a short intervention period of ,12 wk, totaling 12-56 sessions (29,30,32). Most of the included RCTs used a training intensity of 50-80% of participants' one repetition maximum (1-RM) (13, 18, 25-27, 30-34, 37).…”