Whey Protein Support to Metabolic and Performance Adaptations in Response HIIT
Study Details
Study Description
Brief Summary
High intensity interval training (HIIT) has recently emerged as a time efficient alternative to conventional endurance exercise, conferring similar or superior benefits in terms of metabolic and performance adaptations in both athletic and non-athletic populations. Some of these physiological adaptations include augmented mitochondrial biogenesis and improved substrate metabolism in peripheral tissues such as skeletal muscle. However, nutritional strategies to optimise the adaptations to HIIT have yet to be established. Recent evidence suggests that acute nutritional status can affect the molecular regulation of genes mediating substrate metabolism and mitochondrial biogenesis. Moreover, preliminary evidence suggests that completion of exercise in fasted conditions augments some of these exercise-induced adaptations compared with the fed state. Given the fact that the transient molecular adaptations to acute exercise mediate long-term physiological adaptations, an investigation into the effects of different nutritional interventions on metabolic and performance responses to HIIT is warranted.
The purpose of this study is to determine the effects of fasted vs. fed-state (Whey Protein) HIIT on metabolic and performance adaptations in the acute (single exercise session) and chronic (3 weeks, 9 exercise sessions) phases. The primary hypothesis is that different pre-exercise feeding conditions (e.g. fasted placebo vs. Whey protein fed) will result in divergent physiological adaptations in terms of skeletal muscle metabolism and performance, both in response to a single HIIT session and a chronic HIIT intervention.
| Condition or Disease | Intervention/Treatment | Phase |
|---|---|---|
|
N/A |
Detailed Description
High intensity interval training (HIIT) has recently emerged as a time efficient alternative to conventional endurance exercise, conferring similar or superior benefits in terms of metabolic and performance adaptations in both athletic and non-athletic populations. Some of these physiological adaptations include augmented mitochondrial biogenesis and improved substrate metabolism in peripheral tissues such as skeletal muscle. However, nutritional strategies to optimise the adaptations to HIIT have yet to be established. Recent evidence suggests that acute nutritional status can affect the molecular regulation of genes mediating substrate metabolism and mitochondrial biogenesis. Moreover, preliminary evidence suggests that completion of exercise in fasted conditions augments some of these exercise-induced adaptations compared with the fed state. Given the fact that the transient molecular adaptations to acute exercise mediate long-term physiological adaptations, an investigation into the effects of different nutritional interventions on metabolic and performance responses to HIIT is warranted.
The purpose of this study is to determine the effects of fasted vs. fed-state (Whey Protein) HIIT on metabolic and performance adaptations in the acute (single exercise session) and chronic (3 weeks, 9 exercise sessions) phases. The primary hypothesis is that different pre-exercise feeding conditions (e.g. fasted vs. Whey protein fed) will result in divergent physiological adaptations in terms of skeletal muscle metabolism and performance, both in response to a single HIIT session and a chronic HIIT intervention.
A randomly assigned, parallel group, simple pre-post design has been adopted to answer this question. 3 groups of young (aged 18-35 y), healthy, recreationally active, aerobically untrained (VO2max <50 ml.kg.min-1), protein sufficient (>0.8 g.kg.d-1), males will undertake 3 weeks (9 sessions) of HIIT under different nutrient conditions following >10h overnight fast: i) Fasted placebo (0.33g.kg-1 body mass artificially flavoured and textured placebo);
- Fed Whey protein (0.33g.kg-1 body mass intact whey protein 45 minutes prior to exercise);
- Fed Whey protein hydrolysate (0.33g.kg-1 body mass hydrolysed whey protein 45 minutes prior to exercise). Participants will undergo biological sampling (venous blood and muscle biopsy) and measures of performance pre and post the intervention.
Study Design
Arms and Interventions
| Arm | Intervention/Treatment |
|---|---|
| Placebo Comparator: Placebo Intervention (Nutrient support to HIIT): Participants consume 0.33g.kg-1 body mass of artificially flavoured and textured placebo 45 minutes prior to HIIT exercise |
Dietary Supplement: Placebo
3 groups of young (aged 18-35 y), healthy, recreationally active, aerobically untrained (VO2max <50 ml.kg.min-1) males will undertake 3 weeks (9 sessions) of HIIT under different nutrient conditions following >10h overnight fast: i) Fasted artificially flavoured and textured placebo 45 minutes prior to exercise; ii) Fed Whey protein 45 minutes prior to exercise; iii) Fed Whey protein hydrolysate 45 minutes prior to exercise).
|
| Experimental: Whey Protein Intervention (Nutrient support to HIIT): Participants consume 0.33g.kg-1 body mass intact whey protein 45 minutes prior to HIIT exercise |
Dietary Supplement: Nutrient support to HIIT
3 groups of young (aged 18-35 y), healthy, recreationally active, aerobically untrained (VO2max <50 ml.kg.min-1) males will undertake 3 weeks (9 sessions) of HIIT under different nutrient conditions following >10h overnight fast: i) Placebo: Fasted artificially flavoured and textured placebo 45 minutes prior to exercise; ii) Whey protein 45 minutes prior to exercise; iii) Whey protein hydrolysate 45 minutes prior to exercise).
|
| Experimental: Whey Protein Hydrolysate Intervention (Nutrient support to HIIT): Participants consume 0.33g.kg-1 body mass hydrolysed whey protein 45 minutes prior to HIIT exercise |
Dietary Supplement: Nutrient support to HIIT
3 groups of young (aged 18-35 y), healthy, recreationally active, aerobically untrained (VO2max <50 ml.kg.min-1) males will undertake 3 weeks (9 sessions) of HIIT under different nutrient conditions following >10h overnight fast: i) Placebo: Fasted artificially flavoured and textured placebo 45 minutes prior to exercise; ii) Whey protein 45 minutes prior to exercise; iii) Whey protein hydrolysate 45 minutes prior to exercise).
|
Outcome Measures
Primary Outcome Measures
- Organelle Biogenesis (Mitochondrial) Acute [Acute - 3 hours post exercise session 1]
Acute phase - change in Peroxisome Proliferator Activated Receptor 1 alpha (PGC-1α) messenger ribonucleic acid (mRNA) expression in response to a single HIIT session. Measured using real-time polymerase chain reaction (RT-PCR).
- Exercise Performance [Chronic - 72 hours post exercise session 9]
Mean power output (Watts) during 20 minute cycling performance test. Measured using cycle ergometer and associated software.
- Anaerobic Exercise Performance [Chronic - 72 hours post exercise session 9]
Anaerobic exercise performance peak power (Watts). Measured using 30 second Wingate test on a Monark 894E cycle ergometer.
- Organelle Biogenesis (Mitochondrial) Chronic [Chronic - 48 hours post exercise session 9]
Chronic Phase - change in Citrate Synthase Activity measured using commercially available assay kits.
Secondary Outcome Measures
- Organelle Biogenesis (Mitochondrial) [Acute: 3 hours post HIIT session 1.]
Pyruvate Dehydrogenase Kinase 4 (PDK4), Peroxisome Proliferator Activated Receptor (PPAR) delta, Sirtuin 1 (SIRT1) mRNA expression. Measured using real-time polymerase chain reaction (RT-PCR).
- Cycling Economy [Chronic - 72 hours post exercise session 9]
Cycling economy (W.VO2 L.min-1) during multiple incremental stages (50 W, 100 W, 150 W, 200 W, 250 W) of a submaximal cycling test.
Eligibility Criteria
Criteria
Inclusion Criteria:
-
Healthy (absence of clinical condition)
-
Recreationally active
-
Aerobically untrained (VO2max <50 ml.kg.min-1)
-
Protein sufficient (>0.8 g.kg.d-1)
-
Males
-
Able to provide informed consent
-
No contraindications to high intensity exercise
Exclusion Criteria:
-
BMI >30 kg.m-2
-
Metabolic disease (mitochondrial, Type 2 Diabetes)
Contacts and Locations
Locations
| Site | City | State | Country | Postal Code | |
|---|---|---|---|---|---|
| 1 | University of Limerick | Limerick | Munster | Ireland | V94 T9PX |
Sponsors and Collaborators
- University of Limerick
Investigators
- Principal Investigator: Brian P Carson, PhD, University of Limerick
Study Documents (Full-Text)
More Information
Publications
None provided.- 7867835