Protein Supplementation and Skeletal Muscle Healing Process
- Conditions
- Skeletal Muscle DamageIntracellular Signaling in Skeletal MuscleProteasome ActivationExercise-induced Aseptic InflammationSkeletal Muscle Performance
- Interventions
- Dietary Supplement: Milk protein isolateDietary Supplement: Placebo
- Registration Number
- NCT02816411
- Lead Sponsor
- University of Thessaly
- Brief Summary
In this study the investigators utilized protein supplementation over an 8-day period following eccentric exercise-induced muscle damage in order to test the initial hypotheses : i) protein supplementation after exercise-induced muscle injury affects exercise-induced aseptic inflammation and muscle performance.
- Detailed Description
The objective was to examine weather protein supplementation is able to affect the inflammatory response as well as recovery of muscle performance following an intense eccentric exercise protocol. In a double-blind, counterbalanced design, 14 men received either Placebo (PLA) or milk protein isolate (PRO) for 8 consecutive days following a single bout of exercise (300 eccentric contractions at 30 deg/sec). In both conditions, performance was assessed at baseline, immediately post-exercise, 2h post-exercise and daily for 8 consecutive days. Blood samples were collected at baseline, 2h post-exercise and daily for the remaining 8 days. Muscle biopsies from vastus lateralis were collected at baseline as well as at day 2 and day 8 of the post-exercise period.
Recruitment & Eligibility
- Status
- COMPLETED
- Sex
- Male
- Target Recruitment
- 14
- a) recreationally trained as indicated by the maximal oxygen consumption levels (VO2max > 45 ml/kg/min), b) engaged in systematic exercise at least three times per week for > 12 months, c) non-smokers, d) abstained from any vigorous physical activity during the study, e) abstained from consumption of caffeine, alcohol, performance-enhancing or antioxidant supplements, and medications during the study.
- a) a recent febrile illness, b) history of muscle lesion, c) lower limb trauma
Study & Design
- Study Type
- INTERVENTIONAL
- Study Design
- CROSSOVER
- Arm && Interventions
Group Intervention Description Protein Milk protein isolate Milk protein isolate supplementation: orally, 20g of protein immediately post-exercise and then 20g every 3h on 3 occasions (+3, +6, +9), on the exercise day. The remaining 8 days, 20g daily with breakfast. Placebo Placebo Placebo administration: orally 500 ml, immediately post-exercise as well as at +3, +6 and +9 hours, on the exercise day. The remaining 8 days, 500 ml daily with breakfast.
- Primary Outcome Measures
Name Time Method Change in testosterone concentration in plasma 1h before exercise, 2h post-exercise, daily for 8 days post-exercise Changes in volume and morphological complexity of immune cells 1h before exercise, 2h post-exercise, daily for 8 days post-exercise Change in proteasome activities in muscle 1h before exercise, 2 days post-exercise, 8 days post-exercise Measurement of LLVY, LSTR and LLE
Change in creatine kinase activity in plasma 1h before exercise, 2h post-exercise, daily for 8 days post-exercise Change in neutrophil count in blood 1h before exercise, 2h post-exercise, daily for 8 days post-exercise Change in cytokine concentration in plasma 1h before exercise, 2h post-exercise, daily for 8 days post-exercise Measurement of IL-1β, IL-4, IL-6, IL-8, IL-10, TNF-α
Change in total antioxidant capacity in serum 1h before exercise, 2h post-exercise, daily for 8 days post-exercise Total antioxidant capacity in serum
Change in protein expression level of proteasome subunits 1h before exercise, 2 days post-exercise, 8 days post-exercise Measurement of B1i, B2i, B5i, B5, B1, B2 and α7
Change in protein carbonyls in serum 1h before exercise, 2h post-exercise, daily for 8 days post-exercise Concentration of protein carbonyls
Change in thiobarbituric acid and reactive substances in serum 1h before exercise, 2h post-exercise, daily for 8 days post-exercise Thiobarbituric acid reactive substances concentration in serum
Change in white blood cell count in blood 1h before exercise, 2h post-exercise, daily for 8 days post-exercise Change in glucose concentration in blood 1h before exercise, 2h post-exercise, daily for 8 days post-exercise Change in insulin concentration in blood 1h before exercise, 2h post-exercise, daily for 8 days post-exercise Change in adhesion molecule concentration in blood 1h before exercise, 2h post-exercise, daily for 8 days post-exercise Change in reduced glutathione in blood 1h before exercise, 2h post-exercise, daily for 8 days post-exercise Concentration of reduced glutathione in red blood cells
Change in protein carbonyls in muscle 1h before exercise, 2 days post-exercise, 8 days post-exercise Protein carbonyl concentration in quadriceps skeletal muscle group
Change in oxidized glutathione in blood 1h before exercise, 2h post-exercise, daily for 8 days post-exercise Concentration of oxidized glutathione in red blood cells
Change in catalase activity in serum 1h before exercise, 2h post-exercise, daily for 8 days post-exercise Catalase activity in serum
Change in C-reactive protein in plasma 1h before exercise, 2h post-exercise, daily for 8 days post-exercise Change in intracellular signalling proteins in muscle 1h before exercise, 2 days post-exercise, 8 days post-exercise Measurement of phosphorylation levels of mammalian target of rapamycin (mTOR), ribosomal protein S6 (rpS6) and nuclear factor kB (NFkB), and protein expression levels of forkhead box protein O1 (FOXO1), HSP70, and parkin.
- Secondary Outcome Measures
Name Time Method Maximal aerobic capacity One day before exercise Assessment of maximal oxygen consumption
Body composition One day before exercise Assessment of percent (%) body mass
Change in muscle function of knee extensor and flexor muscle 1h before exercise, 5 min post-exercise, 2h post-exercise, daily for 8 days post-exercise Assessment of muscle peak and mean torque of knee extensors and flexors on an isokinetic dynamometer at 0, 90 and 180 degrees/sec
Change in dietary intake profile 1h before exercise, daily for 8 days post-exercise Assessment of dietary intake with emphasis on protein consumption
Trial Locations
- Locations (1)
Exercise Biochemistry Laboratory, School of Physical Education & Sports Sciences, University of Thessaly
🇬🇷Karies, Trikala, Greece