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Three minutes of all-out intermittent exercise per week increases skeletal muscle oxidative capacity and improves cardiometabolic health.

Gillen JB, Percival ME, Skelly LE, Martin BJ, Tan RB, Tarnopolsky MA, Gibala MJ - PLoS ONE (2014)

Bottom Line: Peak oxygen uptake increased by 12% after training (32.6±4.5 vs. 29.1±4.2 ml/kg/min) and resting mean arterial pressure decreased by 7% (78±10 vs. 83±10 mmHg), with no difference between groups (both p<0.01, main effects for time).Skeletal muscle biopsy samples obtained before and 72 h after training revealed increased maximal activity of citrate synthase and protein content of cytochrome oxidase 4 (p<0.01, main effect), while the maximal activity of β-hydroxy acyl CoA dehydrogenase increased in men only (p<0.05).This was associated with a greater increase in GLUT4 protein content in men compared to women (138% vs. 23%, p<0.05).

View Article: PubMed Central - PubMed

Affiliation: Department of Kinesiology, McMaster University, Hamilton, Ontario, Canada.

ABSTRACT
We investigated whether a training protocol that involved 3 min of intense intermittent exercise per week--within a total training time commitment of 30 min including warm up and cool down--could increase skeletal muscle oxidative capacity and markers of health status. Overweight/obese but otherwise healthy men and women (n = 7 each; age = 29±9 y; BMI = 29.8±2.7 kg/m2) performed 18 training sessions over 6 wk on a cycle ergometer. Each session began with a 2 min warm-up at 50 W, followed by 3×20 s "all-out" sprints against 5.0% body mass (mean power output: ∼450-500 W) interspersed with 2 min of recovery at 50 W, followed by a 3 min cool-down at 50 W. Peak oxygen uptake increased by 12% after training (32.6±4.5 vs. 29.1±4.2 ml/kg/min) and resting mean arterial pressure decreased by 7% (78±10 vs. 83±10 mmHg), with no difference between groups (both p<0.01, main effects for time). Skeletal muscle biopsy samples obtained before and 72 h after training revealed increased maximal activity of citrate synthase and protein content of cytochrome oxidase 4 (p<0.01, main effect), while the maximal activity of β-hydroxy acyl CoA dehydrogenase increased in men only (p<0.05). Continuous glucose monitoring measured under standard dietary conditions before and 48-72 h following training revealed lower 24 h average blood glucose concentration in men following training (5.4±0.6 vs. 5.9±0.5 mmol/L, p<0.05), but not women (5.5±0.4 vs. 5.5±0.6 mmol/L). This was associated with a greater increase in GLUT4 protein content in men compared to women (138% vs. 23%, p<0.05). Short-term interval training using a 10 min protocol that involved only 1 min of hard exercise, 3x/wk, stimulated physiological changes linked to improved health in overweight adults. Despite the small sample size, potential sex-specific adaptations were apparent that warrant further investigation.

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Improved indices of blood glucose control in men following very low-volume SIT.GLUT4 protein content measured in muscle biopsy samples obtained from the vastus lateralis before (PRE) and 72 h after (POST) 6 week SIT in men and women (A). Individual 24 h average blood glucose concentration (B) and 24 h blood glucose area under the curve (AUC) measured before (PRE) and 48–72 h after (POST) 6 week SIT in men and women using continuous glucose monitoring (CGM). Values are means ± SD (n = 7 per group for muscle data, n = 6 per group for CGM data). Representative Western blots for 2 men and 2 women are shown for GLUT4. *P<0.05, pre- vs. post-training; +p<0.05, men vs. women at same time point.
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pone-0111489-g004: Improved indices of blood glucose control in men following very low-volume SIT.GLUT4 protein content measured in muscle biopsy samples obtained from the vastus lateralis before (PRE) and 72 h after (POST) 6 week SIT in men and women (A). Individual 24 h average blood glucose concentration (B) and 24 h blood glucose area under the curve (AUC) measured before (PRE) and 48–72 h after (POST) 6 week SIT in men and women using continuous glucose monitoring (CGM). Values are means ± SD (n = 7 per group for muscle data, n = 6 per group for CGM data). Representative Western blots for 2 men and 2 women are shown for GLUT4. *P<0.05, pre- vs. post-training; +p<0.05, men vs. women at same time point.

Mentions: The maximal activity of citrate synthase increased by ∼40% after training (Fig. 3A, main effect for time, p<0.001). COXIV protein content also increased after training with no differences between groups (Fig. 3B, main effect for time, p<0.01), however β-HAD maximal activity only increased after training in the men (Fig. 3C; interaction between training and sex, p<0.05). GLUT4 protein content increased in both men and women following training (Fig. 4A, main effect for time, p<0.01), however men increased to a greater extent compared to women (138% vs. 23%, interaction between training and sex, p<0.05).


Three minutes of all-out intermittent exercise per week increases skeletal muscle oxidative capacity and improves cardiometabolic health.

Gillen JB, Percival ME, Skelly LE, Martin BJ, Tan RB, Tarnopolsky MA, Gibala MJ - PLoS ONE (2014)

Improved indices of blood glucose control in men following very low-volume SIT.GLUT4 protein content measured in muscle biopsy samples obtained from the vastus lateralis before (PRE) and 72 h after (POST) 6 week SIT in men and women (A). Individual 24 h average blood glucose concentration (B) and 24 h blood glucose area under the curve (AUC) measured before (PRE) and 48–72 h after (POST) 6 week SIT in men and women using continuous glucose monitoring (CGM). Values are means ± SD (n = 7 per group for muscle data, n = 6 per group for CGM data). Representative Western blots for 2 men and 2 women are shown for GLUT4. *P<0.05, pre- vs. post-training; +p<0.05, men vs. women at same time point.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4218754&req=5

pone-0111489-g004: Improved indices of blood glucose control in men following very low-volume SIT.GLUT4 protein content measured in muscle biopsy samples obtained from the vastus lateralis before (PRE) and 72 h after (POST) 6 week SIT in men and women (A). Individual 24 h average blood glucose concentration (B) and 24 h blood glucose area under the curve (AUC) measured before (PRE) and 48–72 h after (POST) 6 week SIT in men and women using continuous glucose monitoring (CGM). Values are means ± SD (n = 7 per group for muscle data, n = 6 per group for CGM data). Representative Western blots for 2 men and 2 women are shown for GLUT4. *P<0.05, pre- vs. post-training; +p<0.05, men vs. women at same time point.
Mentions: The maximal activity of citrate synthase increased by ∼40% after training (Fig. 3A, main effect for time, p<0.001). COXIV protein content also increased after training with no differences between groups (Fig. 3B, main effect for time, p<0.01), however β-HAD maximal activity only increased after training in the men (Fig. 3C; interaction between training and sex, p<0.05). GLUT4 protein content increased in both men and women following training (Fig. 4A, main effect for time, p<0.01), however men increased to a greater extent compared to women (138% vs. 23%, interaction between training and sex, p<0.05).

Bottom Line: Peak oxygen uptake increased by 12% after training (32.6±4.5 vs. 29.1±4.2 ml/kg/min) and resting mean arterial pressure decreased by 7% (78±10 vs. 83±10 mmHg), with no difference between groups (both p<0.01, main effects for time).Skeletal muscle biopsy samples obtained before and 72 h after training revealed increased maximal activity of citrate synthase and protein content of cytochrome oxidase 4 (p<0.01, main effect), while the maximal activity of β-hydroxy acyl CoA dehydrogenase increased in men only (p<0.05).This was associated with a greater increase in GLUT4 protein content in men compared to women (138% vs. 23%, p<0.05).

View Article: PubMed Central - PubMed

Affiliation: Department of Kinesiology, McMaster University, Hamilton, Ontario, Canada.

ABSTRACT
We investigated whether a training protocol that involved 3 min of intense intermittent exercise per week--within a total training time commitment of 30 min including warm up and cool down--could increase skeletal muscle oxidative capacity and markers of health status. Overweight/obese but otherwise healthy men and women (n = 7 each; age = 29±9 y; BMI = 29.8±2.7 kg/m2) performed 18 training sessions over 6 wk on a cycle ergometer. Each session began with a 2 min warm-up at 50 W, followed by 3×20 s "all-out" sprints against 5.0% body mass (mean power output: ∼450-500 W) interspersed with 2 min of recovery at 50 W, followed by a 3 min cool-down at 50 W. Peak oxygen uptake increased by 12% after training (32.6±4.5 vs. 29.1±4.2 ml/kg/min) and resting mean arterial pressure decreased by 7% (78±10 vs. 83±10 mmHg), with no difference between groups (both p<0.01, main effects for time). Skeletal muscle biopsy samples obtained before and 72 h after training revealed increased maximal activity of citrate synthase and protein content of cytochrome oxidase 4 (p<0.01, main effect), while the maximal activity of β-hydroxy acyl CoA dehydrogenase increased in men only (p<0.05). Continuous glucose monitoring measured under standard dietary conditions before and 48-72 h following training revealed lower 24 h average blood glucose concentration in men following training (5.4±0.6 vs. 5.9±0.5 mmol/L, p<0.05), but not women (5.5±0.4 vs. 5.5±0.6 mmol/L). This was associated with a greater increase in GLUT4 protein content in men compared to women (138% vs. 23%, p<0.05). Short-term interval training using a 10 min protocol that involved only 1 min of hard exercise, 3x/wk, stimulated physiological changes linked to improved health in overweight adults. Despite the small sample size, potential sex-specific adaptations were apparent that warrant further investigation.

Show MeSH
Related in: MedlinePlus