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Beneficial effects of resistance exercise on glycemic control are not further improved by protein ingestion.

Breen L, Philp A, Shaw CS, Jeukendrup AE, Baar K, Tipton KD - PLoS ONE (2011)

Bottom Line: Plasma insulin response was 13±2 and 21±4% lower for EX and CON, respectively, compared with EX+PRO.Glucose disappearance from the circulation was ∼12% greater in EX and EX+PRO compared with CON.However, co-ingesting protein during a high-glucose load does not augment this response at 24 h post-exercise in healthy, insulin-sensitive individuals.

View Article: PubMed Central - PubMed

Affiliation: School of Sport and Exercise Sciences, University of Birmingham, Birmingham, United Kingdom.

ABSTRACT

Purpose: To investigate the mechanisms underpinning modifications in glucose homeostasis and insulin sensitivity 24 h after a bout of resistance exercise (RE) with or without protein ingestion.

Methods: Twenty-four healthy males were assigned to a control (CON; n = 8), exercise (EX; n = 8) or exercise plus protein condition (EX+PRO; n = 8). Muscle biopsy and blood samples were obtained at rest for all groups and immediately post-RE (75% 1RM, 8×10 repetitions of leg-press and extension exercise) for EX and EX+PRO only. At 24 h post-RE (or post-resting biopsy for CON), a further muscle biopsy was obtained. Participants then consumed an oral glucose load (OGTT) containing 2 g of [U-¹³C] glucose during an infusion of 6, 6-[²H₂] glucose. Blood samples were obtained every 10 min for 2 h to determine glucose kinetics. EX+PRO ingested an additional 25 g of intact whey protein with the OGTT. A final biopsy sample was obtained at the end of the OGTT.

Results: Fasted plasma glucose and insulin were similar for all groups and were not different immediately post- and 24 h post-RE. Following RE, muscle glycogen was 26±8 and 19±6% lower in EX and EX+PRO, respectively. During OGTT, plasma glucose AUC was lower for EX and EX+PRO (75.1±2.7 and 75.3±2.8 mmol·L⁻¹∶120 min, respectively) compared with CON (90.6±4.1 mmol·L⁻¹∶120 min). Plasma insulin response was 13±2 and 21±4% lower for EX and CON, respectively, compared with EX+PRO. Glucose disappearance from the circulation was ∼12% greater in EX and EX+PRO compared with CON. Basal 24 h post-RE and insulin-stimulated PAS-AS160/TBC1D4 phosphorylation was greater for EX and EX+PRO.

Conclusions: Prior RE improves glycemic control and insulin sensitivity through an increase in the rate at which glucose is disposed from the circulation. However, co-ingesting protein during a high-glucose load does not augment this response at 24 h post-exercise in healthy, insulin-sensitive individuals.

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Muscle glycogen content.Values obtained at basal, immediately post-exercise (Post 0), 24 h post-exercise (Post 24) and immediately following OGTT (Post 26). Groups as per Table 1. Values are means ± SEM; n = 6 per group. *: significantly lower compared with basal (P<0.05).
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pone-0020613-g005: Muscle glycogen content.Values obtained at basal, immediately post-exercise (Post 0), 24 h post-exercise (Post 24) and immediately following OGTT (Post 26). Groups as per Table 1. Values are means ± SEM; n = 6 per group. *: significantly lower compared with basal (P<0.05).

Mentions: Basal muscle glycogen concentration was similar for all groups (Figure 5). Immediately post-exercise, muscle glycogen concentration was 26±8 and 19±6% lower for EX and EX+PRO (P<0.05), with no difference between groups. Muscle glycogen concentration at 24 h post-exercise had returned to basal values for all groups. There was no significant change in muscle glycogen concentration following OGTT (∼26 h post-exercise), compared with 24 h post-exercise. The absolute change in muscle glycogen content (Table 4) was greater for EX and EX+PRO compared to CON when measured immediately post-RE-to-24 h post-RE (P<0.01) and during OGTT from 24 h-to-26 h post-RE (P<0.05).


Beneficial effects of resistance exercise on glycemic control are not further improved by protein ingestion.

Breen L, Philp A, Shaw CS, Jeukendrup AE, Baar K, Tipton KD - PLoS ONE (2011)

Muscle glycogen content.Values obtained at basal, immediately post-exercise (Post 0), 24 h post-exercise (Post 24) and immediately following OGTT (Post 26). Groups as per Table 1. Values are means ± SEM; n = 6 per group. *: significantly lower compared with basal (P<0.05).
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Related In: Results  -  Collection

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getmorefigures.php?uid=PMC3119062&req=5

pone-0020613-g005: Muscle glycogen content.Values obtained at basal, immediately post-exercise (Post 0), 24 h post-exercise (Post 24) and immediately following OGTT (Post 26). Groups as per Table 1. Values are means ± SEM; n = 6 per group. *: significantly lower compared with basal (P<0.05).
Mentions: Basal muscle glycogen concentration was similar for all groups (Figure 5). Immediately post-exercise, muscle glycogen concentration was 26±8 and 19±6% lower for EX and EX+PRO (P<0.05), with no difference between groups. Muscle glycogen concentration at 24 h post-exercise had returned to basal values for all groups. There was no significant change in muscle glycogen concentration following OGTT (∼26 h post-exercise), compared with 24 h post-exercise. The absolute change in muscle glycogen content (Table 4) was greater for EX and EX+PRO compared to CON when measured immediately post-RE-to-24 h post-RE (P<0.01) and during OGTT from 24 h-to-26 h post-RE (P<0.05).

Bottom Line: Plasma insulin response was 13±2 and 21±4% lower for EX and CON, respectively, compared with EX+PRO.Glucose disappearance from the circulation was ∼12% greater in EX and EX+PRO compared with CON.However, co-ingesting protein during a high-glucose load does not augment this response at 24 h post-exercise in healthy, insulin-sensitive individuals.

View Article: PubMed Central - PubMed

Affiliation: School of Sport and Exercise Sciences, University of Birmingham, Birmingham, United Kingdom.

ABSTRACT

Purpose: To investigate the mechanisms underpinning modifications in glucose homeostasis and insulin sensitivity 24 h after a bout of resistance exercise (RE) with or without protein ingestion.

Methods: Twenty-four healthy males were assigned to a control (CON; n = 8), exercise (EX; n = 8) or exercise plus protein condition (EX+PRO; n = 8). Muscle biopsy and blood samples were obtained at rest for all groups and immediately post-RE (75% 1RM, 8×10 repetitions of leg-press and extension exercise) for EX and EX+PRO only. At 24 h post-RE (or post-resting biopsy for CON), a further muscle biopsy was obtained. Participants then consumed an oral glucose load (OGTT) containing 2 g of [U-¹³C] glucose during an infusion of 6, 6-[²H₂] glucose. Blood samples were obtained every 10 min for 2 h to determine glucose kinetics. EX+PRO ingested an additional 25 g of intact whey protein with the OGTT. A final biopsy sample was obtained at the end of the OGTT.

Results: Fasted plasma glucose and insulin were similar for all groups and were not different immediately post- and 24 h post-RE. Following RE, muscle glycogen was 26±8 and 19±6% lower in EX and EX+PRO, respectively. During OGTT, plasma glucose AUC was lower for EX and EX+PRO (75.1±2.7 and 75.3±2.8 mmol·L⁻¹∶120 min, respectively) compared with CON (90.6±4.1 mmol·L⁻¹∶120 min). Plasma insulin response was 13±2 and 21±4% lower for EX and CON, respectively, compared with EX+PRO. Glucose disappearance from the circulation was ∼12% greater in EX and EX+PRO compared with CON. Basal 24 h post-RE and insulin-stimulated PAS-AS160/TBC1D4 phosphorylation was greater for EX and EX+PRO.

Conclusions: Prior RE improves glycemic control and insulin sensitivity through an increase in the rate at which glucose is disposed from the circulation. However, co-ingesting protein during a high-glucose load does not augment this response at 24 h post-exercise in healthy, insulin-sensitive individuals.

Show MeSH
Related in: MedlinePlus