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1.
Clin Case Rep ; 11(6): e7548, 2023 Jun.
Article in English | MEDLINE | ID: mdl-37323260

ABSTRACT

Key Clinical Message: In MS patients, especially those frail or malnourished, combining home-based exercise twice weekly with essential amino acids and vitamin D may improve body composition, strength, and physical performance, enabling long-term functional improvements. Abstract: Multiple sclerosis (MS) is associated with reduced bone and muscle strength and function. We aimed to investigate the effectiveness of a 24-week intervention in a 57-year-old frail female with MS. The participant completed a 2×/week exercise intervention and ingested 2×/day a supplement containing 7.5 g essential amino acids and 500 IU cholecalciferol. Body composition, 6-m gait speed (GS), handgrip strength (HGS), 30-sec arm-curl test (30ACT), 6-min walking test (6MWT), 30-sec chair-stand test (30CST), and plasma concentrations of 25-hydroxyvitamin D3 [25(OH)D3], insulin-like growth factor 1 (IGF-1), and amino acids were assessed at baseline, and at Weeks 12 and 24. Plasma 25(OH)D3 increased from 23.2 to 41.3 ng/mL and IGF-1 from 131.6 to 140.7 ng/mL from baseline to post-intervention. BMI, total lean tissue mass (LTM), fat mass, bone mineral content, and the sum of 17 amino acids increased by 3.8, 1.0, 3.5, 0.2, and 19%, respectively, at Week 24. There were clinically significant increases in regional LTM (6.9% arms and 6.3% legs) and large increases in GS (67.3%), dominant HGS (31.5%), non-dominant HGS (11.8%), dominant 30ACT (100%), non-dominant 30ACT (116.7%), 6MWT (125.6%), and 30CST (44.4%). The current intervention was effective in improving components of physical fitness and body composition in a female with MS.

2.
Proc Nutr Soc ; 80(2): 230-242, 2021 05.
Article in English | MEDLINE | ID: mdl-33315000

ABSTRACT

The primary aim of this review is to evaluate the efficacy of essential amino acid (EAA) supplementation as a strategy to increase dietary protein intake and improve muscle mass, strength and function in older adults. A sufficient daily protein intake is widely recognised to be fundamental for the successful management of sarcopenia in older undernourished adults. In practice, optimising protein intakes in older adults is complex, requiring consideration of the dose and amino acid composition (i.e. a complete EAA profile and abundant leucine content) of ingested protein on a per meal basis, alongside the age-related decline in appetite and the satiating properties of protein. Recent studies in older adults demonstrate that EAA-based supplements are non-satiating and can be administered alongside food to enhance the anabolic properties of a meal containing a suboptimal dose of protein; an effect magnified when combined with resistance exercise training. These findings support the notion that EAA supplementation could serve as an effective strategy to improve musculoskeletal health in older adults suffering from non-communicable diseases such as sarcopenia. Compliance is critical for the long-term success of complex interventions. Hence, aspects of palatability and desire to eat are important considerations regarding EAA supplementation. In conclusion, EAA-based supplements enriched with l-leucine offer an alternative strategy to whole protein sources to assist older adults in meeting protein recommendations. In practice, EAA supplements could be administered alongside meals of suboptimal protein content, or alternatively between meals on occasions when older adults achieve their per meal protein intake recommendations.


Subject(s)
Dietary Proteins , Sarcopenia , Aged , Dietary Supplements , Humans , Leucine , Muscle Strength , Muscle, Skeletal , Sarcopenia/drug therapy , Sarcopenia/prevention & control
3.
Nutrients ; 12(7)2020 Jul 12.
Article in English | MEDLINE | ID: mdl-32664648

ABSTRACT

We investigated the effects of ingesting a leucine-enriched essential amino acid (EAA) gel alone or combined with resistance exercise (RE) versus RE alone (control) on plasma aminoacidemia and intramyocellular anabolic signaling in healthy younger (28 ± 4 years) and older (71 ± 3 years) adults. Blood samples were obtained throughout the three trials, while muscle biopsies were collected in the postabsorptive state and 2 h following RE, following the consumption of two 50 mL EAA gels (40% leucine, 15 g total EAA), and following RE with EAA (combination (COM)). Protein content and the phosphorylation status of key anabolic signaling proteins were determined via immunoblotting. Irrespective of age, during EAA and COM peak leucinemia (younger: 454 ± 32 µM and 537 ± 111 µM; older: 417 ± 99 µM and 553 ± 136 µM) occurred ~60-120 min post-ingestion (younger: 66 ± 6 min and 120 ± 60 min; older: 90 ± 13 min and 78 ± 12 min). In the pooled sample, the area under the curve for plasma leucine and the sum of branched-chain amino acids was significantly greater in EAA and COM compared with RE. For intramyocellular signaling, significant main effects were found for condition (mTOR (Ser2481), rpS6 (Ser235/236)) and age (S6K1 (Thr421/Ser424), 4E-BP1 (Thr37/46)) in age group analyses. The phosphorylation of rpS6 was of similar magnitude (~8-fold) in pooled and age group data 2 h following COM. Our findings suggest that a gel-based, leucine-enriched EAA supplement is associated with aminoacidemia and a muscle anabolic signaling response, thus representing an effective means of stimulating muscle protein anabolism in younger and older adults following EAA and COM.


Subject(s)
Aging/metabolism , Amino Acids, Essential/administration & dosage , Amino Acids, Essential/blood , Dietary Supplements , Exercise/physiology , Muscle Proteins/metabolism , Muscle, Skeletal/metabolism , Resistance Training , Adult , Aged , Amino Acids, Essential/metabolism , Female , Humans , Leucine/administration & dosage , Leucine/blood , Leucine/metabolism , Male , Mechanistic Target of Rapamycin Complex 1/metabolism , Sarcopenia/metabolism , Young Adult
4.
Appl Physiol Nutr Metab ; 44(11): 1141-1149, 2019 Nov.
Article in English | MEDLINE | ID: mdl-30835491

ABSTRACT

Deficiencies in protein and energy intakes are partly responsible for age-related sarcopenia. We investigated the effects of supplements matched in essential amino acid (EAA) content (7.5 g) on energy intake and appetite. Ten women aged 69.2 ± 2.7 years completed 3 trials in a randomised, crossover design. Composite appetite scores, peptide-YY (PYY), and insulin responses to a 200-mL whey protein (WP) isolate (275 kJ), a 50-mL EAA gel (GEL, 478 kJ), or nothing as the control (CON) condition were investigated over 1 h, followed by an ad libitum breakfast. Energy intake at breakfast (CON, 1957 ± 713; WP, 1413 ± 623; GEL, 1963 ± 611 kJ) was higher in CON and GEL than in WP (both P = 0.006). After accounting for supplement energy content, energy intake in GEL was higher than in CON (P = 0.0006) and WP (P = 0.0008). Time-averaged area under the curve for composite appetite scores (CON, 74 ± 20; WP, 50 ± 22; GEL, 60 ± 16 mm) was higher in CON than WP (P = 0.015). Time-averaged area under the curve for PYY (CON, 87 ± 13; WP, 119 ± 27; GEL, 97 ± 22 pg·mL-1) was higher in WP than CON (P = 0.009) and GEL (P = 0.012). In conclusion, supplementation with WP facilitated an increase in protein intake, whereas supplementation with GEL increases in both energy and protein intakes, when consumed before an ad libitum breakfast. Such findings highlight potential gel-based EAA supplementation intake for addressing age-related sarcopenia.


Subject(s)
Amino Acids, Essential/administration & dosage , Appetite , Dietary Supplements , Energy Intake , Whey Proteins/administration & dosage , Aged , Cross-Over Studies , Female , Gels , Humans , Insulin/blood , Peptide YY/blood
5.
Nutr J ; 16(1): 75, 2017 Nov 28.
Article in English | MEDLINE | ID: mdl-29183324

ABSTRACT

BACKGROUND: Inadequate protein intake (PI), containing a sub-optimal source of essential amino acids (EAAs), and reduced appetite are contributing factors to age-related sarcopenia. The satiating effects of dietary protein per se may negatively affect energy intake (EI), thus there is a need to explore alternative strategies to facilitate PI without compromising appetite and subsequent EI. METHODS: Older women completed two experiments (EXP1 and EXP2) where they consumed either a Bar (565 kJ), a Gel (477 kJ), both rich in EAAs (7.5 g, 40% L-leucine), or nothing (Control). In EXP1, participants (n = 10, 68 ± 5 years, mean ± SD) consumed Bar, Gel or Control with appetite sensations and appetite-related hormonal responses monitored for one hour, followed by consumption of an ad libitum breakfast (ALB). In EXP2, participants (n = 11, 69 ± 5 years) ingested Bar, Gel or Control alongside an ALB. RESULTS: In EXP1, EI at ALB was not different (P = 0.674) between conditions (1179 ± 566, 1254 ± 511, 1206 ± 550 kJ for the Control, Bar, and Gel respectively). However, total EI was significantly higher in the Bar and Gel compared to the Control after accounting for the energy content of the supplements (P < 0.0005). Analysis revealed significantly higher appetite Area under the Curve (AUC) (P < 0.007), a tendency for higher acylated ghrelin AUC (P = 0.087), and significantly lower pancreatic polypeptide AUC (P = 0.02) in the Control compared with the Bar and Gel. In EXP2, EI at ALB was significantly higher (P = 0.028) in the Control (1282 ± 513 kJ) compared to the Bar (1026 ± 565 kJ) and Gel (1064 ± 495 kJ). However, total EI was significantly higher in the Bar and Gel after accounting for the energy content of the supplements (P < 0.007). CONCLUSIONS: Supplementation with either the Bar or Gel increased total energy intake whether consumed one hour before or during breakfast. This may represent an effective nutritional means for addressing protein and total energy deficiencies in older women. TRIAL REGISTRATION: Clinical trial register: retrospectively registered, ISRCTN12977929 on.


Subject(s)
Amino Acids, Essential/administration & dosage , Dietary Proteins/administration & dosage , Dietary Supplements , Energy Intake , Leucine/administration & dosage , Aged , Aged, 80 and over , Amino Acids, Essential/blood , Anthropometry , Appetite , Breakfast , C-Reactive Protein/metabolism , Cross-Over Studies , Female , Ghrelin/blood , Humans , Leucine/blood , Middle Aged , Pancreatic Polypeptide/blood , Peptide YY/blood
6.
Int J Sports Physiol Perform ; 6(1): 38-50, 2011 Mar.
Article in English | MEDLINE | ID: mdl-21487148

ABSTRACT

PURPOSE: To investigate the effects of daily oral L-leucine ingestion on strength, bone mineral-free lean tissue mass (LTM) and fat mass (FM) of free living humans during a 12-wk resistance-training program. METHODS: Twenty-six initially untrained men (n = 13 per group) ingested either 4 g/d of L-leucine (leucine group: age 28.5 ± 8.2 y, body mass index 24.9 ± 4.2 kg/m2) or a corresponding amount of lactose (placebo group: age 28.2 ± 7.3 y, body mass index 24.9 ± 4.2 kg/m2). All participants trained under supervision twice per week following a prescribed resistance training program using eight standard exercise machines. Testing took place at baseline and at the end of the supplementation period. Strength on each exercise was assessed by five repetition maximum (5-RM), and body composition was assessed by dual energy X-ray absorptiometry (DXA). RESULTS: The leucine group demonstrated significantly higher gains in total 5-RM strength (sum of 5-RM in eight exercises) and 5-RM strength in five out of the eight exercises (P < .05). The percentage total 5-RM strength gains were 40.8% (± 7.8) and 31.0% (± 4.6) for the leucine and placebo groups respectively. Significant differences did not exist between groups in either total percentage LTM gains or total percentage FM losses (LTM: 2.9% ± 2.5 vs 2.0% ± 2.1, FM: 1.6% ± 15.6 vs 1.1% ± 7.6). CONCLUSION: These results suggest that 4 g/d of L-leucine supplementation may be used as a nutritional supplement to enhance strength performance during a 12-week resistance training program of initially untrained male participants.


Subject(s)
Dietary Supplements , Leucine/administration & dosage , Muscle Strength/drug effects , Resistance Training , Weight Lifting , Absorptiometry, Photon , Administration, Oral , Adult , Biomarkers/blood , Body Composition/drug effects , Body Mass Index , Double-Blind Method , Drug Administration Schedule , Energy Intake , Humans , Male , Perception , Time Factors , Young Adult
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