MedPath

The Effects of Whey Protein Supplements on Markers of Exercise-induced Muscle Damage in Resistance-trained Individuals

Not Applicable
Completed
Conditions
Muscle Soreness
Muscle Damage
Interventions
Dietary Supplement: Conventional whey protein
Dietary Supplement: Pasture-raised whey protein
Dietary Supplement: Placebo
Registration Number
NCT05100459
Lead Sponsor
Indiana University
Brief Summary

Intense exercise can bring about various side effects to one's body. Less range of motion, increased pain sensitivity, increased muscle swelling, and decreased muscle strength can occur immediately after exercise. These side effects can be referred to exercise induced muscle damage (EIMD) and can sometimes last many days. This study's goal is to evaluate the effects of various protein supplements on EIMD symptoms as well as on blood vessel health during the recovery period after muscle damaging exercise.

Detailed Description

Eccentric exercise can result in exercise induced muscle damage (EIMD), which can cause an abundance of ultrastructural muscular disruption and pro-inflammatory and pro-oxidant activity in the body, leading to an impairment of muscular force production and range of motion, along with elevated pain sensitivity, increased swelling, and arterial stiffness. Pasture-raised dairy products, obtained from strictly grass-fed cows, have been shown to possess more anti-inflammatory-, antioxidant-, and antihypertensive-like biochemicals compared with conventional products (i.e., with a different nutrient composition from a diet rich in grains versus grasses). However, human research trials on these products, such as whey protein concentrate (WPC), are neglected. This study addresses this gap, with a double-blind, randomized, placebo-controlled trial that compares the effect of conventional WPC versus WPC supplementation reported to be derived from pasture-raised cows on vascular function and indirect markers of muscle damage and inflammation in response to eccentric EIMD in healthy, young, resistance-trained women and men. Thirty resistance-trained individuals will complete an intense EIMD bout consisting of eccentric barbell back squats and then will be assessed 24, 48, and 72 hours post-EIMD for muscle soreness, range of motion, maximal isometric voluntary contraction, peripheral fatigue via magnetic stimulation, countermovement jump, barbell back squat velocity, and vascular function (i.e., arterial stiffness via carotid femoral pulse wave velocity). Subjects will be grouped into a conventional WPC, pasture-raised WPC, and placebo supplementation group and consume their respective supplementation thrice daily immediately post-EIMD until the study's completion.

Recruitment & Eligibility

Status
COMPLETED
Sex
All
Target Recruitment
39
Inclusion Criteria
  • Men and women 18-40 years old
  • ≥3 months uninterrupted training of ≥3 days/week of resistance training
  • Self-reported to be healthy
Exclusion Criteria
  • Not within defined age range
  • History of allergy to dairy products
  • History of experiencing pain while exercising in the lower extremities (i.e., hips/knees)
  • Current use of anti-inflammatory/anti-pain medication (i.e., nonsteroidal anti-inflammatory drugs (NSAIDs) such as Tylenol, Advil, or Aleve
  • Are pregnant or could possibly be pregnant by self-report
  • People who answer 'yes' to any of the pre-participation screening questions on the PAR-Q questionnaire.

Study & Design

Study Type
INTERVENTIONAL
Study Design
PARALLEL
Arm && Interventions
GroupInterventionDescription
Conventional whey proteinConventional whey proteinwhey protein from conventional animal feeding operation
Pasture-raised whey proteinPasture-raised whey proteinwhey protein from strictly grass fed cows
PlaceboPlaceboMaltodextrin given in iso-caloric amounts to protein
Primary Outcome Measures
NameTimeMethod
Range of motionFour days

Hamstring flexibility and stiffness will be measured using a sit-and-reach box (Lafayette Instrument Company, Lafayette, IN) test. Units: cm

Isometric torqueFour days

Isometric torque assessment of right leg extensors will be conducted at a knee angle of 90 degrees using a calibrated load cell (model Z Tension Load Cell; Dillon, Fairmont, MN) Units: Nm

TitinFour days

Muscle damage assessment via urinary titin via ELISA (MBS2881644, Human Titin ELISA® Kit, MyBioSource.com, Inc., San Diego, USA). Units: pmol

delayed onset muscle sorenessFour days

Visual analog scale of muscle soreness (delayed onset muscle soreness; DOMS) - Knee extensor soreness will be assessed using a visual analogue scale with "no soreness" indicated at one end (score 0) and "unbearably painful" at the other (score 100). Units: arbitrary units

Peripheral FatigueFour days

Peripheral fatigue will be assessed via magnetic stimulation (Magstim 200-2; Jali Medical, Newton, MA, USA) of the femoral nerve, which will be used to elicit a quadriceps twitch. Units: Nm

Barbell back squat velocityFour days

The mean velocity of the barbell will be measured using the linear position transducer as per the load velocity profile relationship. Units: m/s

Pain pressure thresholdFour days

Muscle tenderness, known as pain pressure threshold, will be quantified using a digital algometer (Force One, Wagner Instruments, Greenwich, CT) on pre-marked sites at two specific points on the quadriceps (rectus femoris-RF and vastus lateralis-VL) and one on the calf (gastrocnemius-GM). Units: percentage change from baseline

Countermovement JumpFour days

A linear position transducer (GymAware Powertool; Kinetic Performance Technology, Canberra, Australia) interfaced with an iPad (Apple, CA, USA) will be used to calculate countermovement jump (CMJ) height. Units: cm

Secondary Outcome Measures
NameTimeMethod
Arterial StiffnessFour days

Utilizing carotid femoral pulse wave velocity via applanation tonometry, considered the non-invasive gold standard of central arterial stiffness, the ATCOR SphygmoCor® (Naperville, IL, USA) device will be utilized. Units: m/sec

Trial Locations

Locations (1)

Indiana University School of Public Health

🇺🇸

Bloomington, Indiana, United States

© Copyright 2025. All Rights Reserved by MedPath