0000000000038476

AUTHOR

Jeff S. Volek

showing 36 related works from this author

Effects of Stretching on Upper-Body Muscular Performance

2008

The purpose of this investigation was to examine the influence of upper-body static stretching and dynamic stretching on upper-body muscular performance. Eleven healthy men, who were National Collegiate Athletic Association Division I track and field athletes (age, 19.6 +/- 1.7 years; body mass, 93.7 +/- 13.8 kg; height, 183.6 +/- 4.6 cm; bench press 1 repetition maximum [1RM], 106.2 +/- 23.0 kg), participated in this study. Over 4 sessions, subjects participated in 4 different stretching protocols (i.e., no stretching, static stretching, dynamic stretching, and combined static and dynamic stretching) in a balanced randomized order followed by 4 tests: 30% of 1 RM bench throw, isometric ben…

AdultMaleOrthodonticsAMAXUpper bodyRepetition maximumPhysical Therapy Sports Therapy and RehabilitationGeneral MedicineIsometric exerciseAthletic PerformanceBench pressDynamic stretchingUpper ExtremityStatic stretchingMuscle Stretching ExercisesExercise TestHumansOrthopedics and Sports MedicineMuscle SkeletalThrowingMathematicsJournal of Strength and Conditioning Research
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Exercise and Recovery Responses of Lymphokines to Heavy Resistance Exercise

2000

To examine the effect of dynamic resistance exercise on the response patterns of lymphokines, 10 strength-trained men (21.7 +- 0.6 y) performed 2 resistance exercise protocols, high force (HF) and high power (HP), of equal total work (HF 5 33.0 +- 2.5 kJ; HP 5 33.3 +- 2.7 kJ) in a randomized order separated by 1 week. Resting blood samples were obtained preexercise and 0 (R-0), 15 (R-15), and 240 (R-240) minutes postexercise. Plasma lactate significantly (p < 0.05) increased from baseline for both protocols; however, concentrations were higher in response to the HF protocol. Plasma interleukin- 2 (IL-2) concentrations were significantly decreased from baseline at R-15 following the HF proto…

medicine.medical_specialtyTotal workChemistryLymphokineResistance trainingInterleukinPhysical Therapy Sports Therapy and RehabilitationGeneral MedicineDynamic resistanceHigh resistanceEndocrinologyInternal medicineImmunologymedicineOrthopedics and Sports MedicineAcute stressThe Journal of Strength and Conditioning Research
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The effects of amino acid supplementation on hormonal responses to resistance training overreaching.

2005

The purpose of this investigation was to examine the effects of amino acid supplementation on muscular performance and resting hormone concentrations during resistance training overreaching. Seventeen resistance-trained men were randomly assigned to either an amino acid (AA) or a placebo (P) group and underwent 4 weeks of total-body resistance training designed to induce a state of overreaching. The protocol consisted of two 2-week phases (phase 1, 3 sets of 8 exercises performed for 8-12 repetitions; phase 2, 5 sets of 5 exercises performed for 3-5 repetitions). Muscle strength and resting blood samples were determined before (T1) and at the end of each training week (T2-T5). One-repetitio…

AdultMalemedicine.medical_specialtyGlobulinAnabolismHydrocortisoneEndocrinology Diabetes and MetabolismBench presschemistry.chemical_compoundHemoglobinsEndocrinologyDouble-Blind MethodInternal medicineSex Hormone-Binding GlobulinmedicineHumansTestosteroneAmino AcidsInsulin-Like Growth Factor ICreatine KinaseTestosteroneExercise TolerancebiologyHuman Growth HormoneOverreachingHormonesPeptide FragmentsUric AcidEndocrinologychemistryDietary Supplementsbiology.proteinUric acidCreatine kinaseHormoneMetabolism: clinical and experimental
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Leukocyte β2-Adrenergic Receptor Expression in Response to Resistance Exercise

2011

Purpose: Epinephrine and norepinephrine mediate interactions between the neuroendocrine and the immune systems to alter immune cell activity. Although both systems respond to exercise stress, less is known about how they interact in response to such stress. The purpose of this investigation was to examine s2-adrenergic receptor (s2-ADR) expression on circulating leukocytes to an acute bout of resistance exercise in men and women. Methods: Resistance-trained men (n = 8; mean ± SD age = 24.63 ± 5.07 yr, body mass index = 26.09 ± 2.21 kg·m-2) and women (n = 7; age = 22.13 ± 3.09 yr, body mass index = 22.63 ± 2.03 kg·m-2) performed an acute resistance exercise protocol (six sets of five-repetit…

AdultMalemedicine.medical_specialtyAdolescentEpinephrineAdrenergicPhysical Therapy Sports Therapy and RehabilitationBody Mass IndexFlow cytometryNorepinephrine (medication)NorepinephrineYoung AdultImmune systemInternal medicineLeukocytesmedicineHumansOrthopedics and Sports MedicineLactic AcidYoung adultReceptormedicine.diagnostic_testbusiness.industryResistance TrainingEpinephrineEndocrinologyFemaleReceptors Adrenergic beta-2businessBody mass indexmedicine.drugMedicine &amp; Science in Sports &amp; Exercise
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Androgen receptors and testosterone in men—Effects of protein ingestion, resistance exercise and fiber type

2007

The purpose of this study was to examine the impact of protein ingestion on circulating testosterone and muscle androgen receptor (AR) as well as on insulin-like growth factor-I (MGF and IGF-IEa) responses to a resistance exercise (RE) bout in (57-72 year) men. Protein (15 g whey) (n=9) or placebo (n=9) was consumed before and after a RE bout (5 sets of 10 repetition maximums), and vastus lateralis muscle biopsies were taken pre, 1 and 48 h post-RE. The protein ingestion blunted the RE-induced increase in serum free and total testosterone while the RE bout significantly increased muscle AR mRNA levels in older men (P<0.05). However, protein ingestion did not significantly affect AR mRNA or …

AdultMalemedicine.medical_specialtyVastus lateralis muscleEndocrinology Diabetes and MetabolismBlotting WesternMuscle Fibers SkeletalClinical BiochemistryBiologyBiochemistryMuscle hypertrophyEndocrinologyDouble-Blind MethodInternal medicineGene expressionmedicineHumansTestosteroneRNA MessengerExercise physiologyReceptorExerciseMolecular BiologyTestosteroneReverse Transcriptase Polymerase Chain ReactionAge FactorsSkeletal muscleCell BiologyMiddle AgedImmunohistochemistryAndrogen receptormedicine.anatomical_structureEndocrinologyReceptors AndrogenMolecular MedicineDietary ProteinsThe Journal of Steroid Biochemistry and Molecular Biology
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Changes in Exercise Performance and Hormonal Concentrations Over a Big Ten Soccer Season in Starters and Nonstarters

2004

As a consequence of the physiological demands experienced during a competitive soccer season, the antagonistic relationship between anabolic and catabolic processes can affect performance. Twenty-five male collegiate soccer players were studied throughout a season (11 weeks) to investigate the effects of long-term training and competition. Subjects were grouped as starters (S; n = 11) and nonstarters (NS; n = 14). Measures of physical performance, body composition, and hormonal concentrations (testosterone [T] and cortisol [C]) were assessed preseason (T1) and 5 times throughout the season (T2-T6). Starters and NS participated in 83.06% and 16.95% of total game time, respectively. Nonstarte…

medicine.medical_specialtyKnee extensorsAnabolismOvertrainingbusiness.industryPhysical Therapy Sports Therapy and RehabilitationGeneral Medicinemedicine.diseaseVertical jumpAnimal scienceSprintExercise performancemedicinePhysical therapyOrthopedics and Sports Medicinebusinesshuman activitiesTestosteroneHormoneThe Journal of Strength and Conditioning Research
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Factors Affecting Flutter Kicking Speed in Women Who Are Competitive and Recreational Swimmers

2009

The purpose of this study was to determine the relationships between possible predictive measures of a 50 m front crawl swimming and a 22.86 m flutter kicking speed. Ten women who were National Collegiate Athletic Association Division I collegiate swimmers and 10 women who were recreational swimmers (mean +/- SD = 20.6 +/- 1.6 years; 66.7 +/- 10.3 kg; 166.7 +/- 8.8 cm) volunteered for the study. Anthropometric measures were obtained including height, leg length, lower leg length, and foot length. Ankle flexibility was assessed by measuring ankle plantar flexion and ankle inversion. Lower body power was measured using a vertical jump. Swimming and kicking speed were measured as the time to c…

medicine.medical_specialtyFlexibility (anatomy)Ankle inversionPhysical Therapy Sports Therapy and RehabilitationAthletic PerformanceYoung AdultVertical jumpmental disordersmedicineHumansOrthopedics and Sports MedicineRange of Motion ArticularSwimmingAgedLegGeneral Medicinebody regionsmedicine.anatomical_structurePhysical therapyFlutterFemaleAnklePsychologyRange of motionhuman activitiesFront crawlAnkle JointLower Leg LengthJournal of Strength and Conditioning Research
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The effect of heavy resistance exercise on the circadian rhythm of salivary testosterone in men.

2001

Circadian rhythms of serum testosterone concentrations in men have been shown, in general, to be highest in the morning and lowest in the evening. Thus, the purpose of this investigation was to determine the effects of acute resistance exercise upon the waking circadian rhythm of salivary testosterone over 2 days (with or without resistance exercise). The subjects included ten resistance-trained men (with at least 1 year of lifting experience) with the following characteristics [mean (SD)]: age 21.6 (1.1) years; height 177.8 (9.5) cm; body mass 80.5 (11.5) kg; percent body fat 7.9 (1.7)%. A matched, randomized, crossover study design was used such that each subject was tested under both the…

AdultMalemedicine.medical_specialtyEveningWeight LiftingPhysiologyStrength trainingPhysical exercisePhysiology (medical)Internal medicinemedicineHumansOrthopedics and Sports MedicineTestosteroneCircadian rhythmExercise physiologySalivaExerciseMorningChronobiologyCross-Over Studiesbusiness.industryPublic Health Environmental and Occupational HealthGeneral MedicineCrossover studyCircadian RhythmEndocrinologybusinessEuropean journal of applied physiology
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Acute hormonal responses to heavy resistance exercise in younger and older men

1998

The purpose of this investigation was to examine the acute responses of several hormones [total and free testosterone (TT and FT, respectively), adrenocorticotropic hormone (ACTH), cortisol (C), growth hormone (GH), and insulin (INS)] to a single bout of heavy resistance exercise (HRE). Eight younger [30-year (30y) group] and nine older [62-year (62y) group] men matched for general physical characteristics and activity levels performed four sets of ten repetitions maximum (RM) squats with 90 s rest between sets. Blood samples were obtained from each subject via an indwelling cannula with a saline lock pre-exercise, immediately post-exercise (IP), and 5, 15 and 30 min post-exercise. Levels o…

AdultBlood GlucoseMaleAgingmedicine.medical_specialtyHydrocortisoneWeight LiftingPhysiologymedicine.medical_treatmentPhysical exerciseAdrenocorticotropic hormoneAdrenocorticotropic HormonePhysiology (medical)Internal medicinemedicineHumansInsulinEndocrine systemTestosteroneOrthopedics and Sports MedicineLactic AcidSalineTestosteroneHuman Growth Hormonebusiness.industryInsulinPublic Health Environmental and Occupational HealthArea under the curveGeneral MedicineMiddle AgedHormonesEndocrinologybusinessHormoneEuropean Journal of Applied Physiology
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The effects of a roundtrip trans-American jet travel on physiological stress, neuromuscular performance, and recovery.

2016

The purpose was to examine the effects of a round trip trans-American jet travel on performance, hormonal alterations, and recovery. Ten matched pairs of recreationally trained men were randomized to either a compression group (COMP) ( n = 10; age: 23.1 ± 2.4 yr; height: 174.8 ± 5.3 cm; body mass: 84.9 ± 10.16 kg; body fat: 15.3 ± 6.0%) or control group (CONT) ( n = 9; age: 23.2 ± 2.3 yr; height: 177.5 ± 6.3 cm; weight: 84.3 ± 8.99 kg; body fat: 15.1 ± 6.4%). Subjects flew directly from Hartford, CT to Los Angeles, CA 1 day before a simulated sport competition (SSC) designed to create muscle damage and returned the next morning on an overnight flight back home. Both groups demonstrated jet…

AdultMalemedicine.medical_specialtyInjury controlPhysiologyAccident preventionPoison controlAthletic Performancecircadian patternspower03 medical and health sciences0302 clinical medicinePhysical medicine and rehabilitationStress PhysiologicalPhysiology (medical)medicineHumansta315Physiological stressIntermittent Pneumatic Compression DevicesJet Lag SyndromeJet (fluid)TravelSleep qualitymuscular performance030229 sport sciencesRecovery of FunctionHormonesUnited StatesSurgeryCircadian Rhythmendocrine systemMuscle FatigueFemaleneuromuscularPsychologySleepumpieritys030217 neurology & neurosurgeryJournal of applied physiology (Bethesda, Md. : 1985)
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Elevated endogenous testosterone concentrations potentiate muscle androgen receptor responses to resistance exercise.

2009

The purpose of this study was to determine the influence of endogenous circulating testosterone (T) on muscle androgen receptor (AR) responses to acute resistance exercise (RE). Six healthy men (26+/-4 years; 176+/-5 cm; 75.8+/-11.4 kg) performed a knee extension exercise protocol on two occasions separated by 1-3 weeks. Rest preceded one trial (i.e., control [CON] trial) and a high-volume upper-body RE protocol designed to increase circulating T preceded the other trial (i.e., high T [HT] trial). Serial blood samples were obtained throughout each trial to determine circulating T concentrations. Biopsies of the vastus lateralis were obtained pre-RE (REST), 10-min post-RE (+10), and 180-min …

AdultMalemedicine.medical_specialtyTime FactorsAnabolismmedicine.drug_classEndocrinology Diabetes and MetabolismRestClinical BiochemistryBiologyBiochemistryQuadriceps MuscleYoung AdultEndocrinologyInternal medicinemedicineHumansTestosteroneExercise physiologyReceptorMuscle SkeletalMolecular BiologyExerciseTestosteroneCell BiologyAndrogenAndrogen receptorEndocrinologyReceptors AndrogenArea Under CurveMolecular Medicinemedicine.symptomHormoneMuscle contractionThe Journal of steroid biochemistry and molecular biology
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Influence of HMB Supplementation and Resistance Training on Cytokine Response to Resistance Exercise

2014

The purpose of this study was to determine the effects of a multinutritional supplement including amino acids, β-hydroxy-β-methylbutyrate (HMB), and carbohydrates on cytokine responses to resistance exercise and training.Seventeen healthy, college-aged men were randomly assigned to a Muscle Armor™ (MA; Abbott Nutrition, Columbus, OH) or placebo supplement group and 12 weeks of resistance training. An acute resistance exercise protocol was administered at 0, 6, and 12 weeks of training. Venous blood samples at pre-, immediately post-, and 30-minutes postexercise were analyzed via bead multiplex immunoassay for 17 cytokines.After 12 weeks of training, the MA group exhibited decreased interfer…

Malemedicine.medical_specialtyStrength trainingmedicine.medical_treatmentInterleukin-1betaMedicine (miscellaneous)Immune functionGranulocytePlaceboBody Mass IndexInterferon-gammaYoung AdultDouble-Blind MethodMuscle damageInternal medicineMyokineMyokinemedicineDietary CarbohydratesValeratesHumansMicronutrientsAmino Acidsta315Chemokine CCL4Immune function; Muscle damage; Myokine; Nutrition; Strength trainingChemokine CCL2NutritionNutrition and DieteticsInterleukin-13business.industryInterleukin-6MonocyteBody WeightInterleukin-8InterleukinResistance TrainingVenous bloodHealthy VolunteersInterleukin-10Cytokinemedicine.anatomical_structureEndocrinologyNutrition AssessmentImmunologyDietary SupplementsCytokinesStrength trainingbusiness
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Serum basal hormone concentrations and muscle mass in aging women: Effects of strength training and diet

2006

This study examined the effects of strength training and diet on serum basal hormone concentrations and muscle mass in aging women. Fifty-one women age 49 to 74 y were divided into two groups: strength training and nutritional counseling (n = 25), and strength training (n = 26). Both groups performed strength training twice a week for 21 wk. Nutritional counseling was given to attain sufficient energy and protein intake and recommended intake of fat and fiber. We found that the cross-sectional area of the quadriceps femoris increased by 9.5 ± 4.1% in the nutritional counseling group versus 6.8 ± 3.5% in the strength training only group after training (P &lt; 0.052). Nutritional counseling e…

Agingmedicine.medical_specialtyWeight LiftingGlobulinStrength trainingeducationMedicine (miscellaneous)Muscle massBasal (phylogenetics)Sex Hormone-Binding GlobulinInternal medicinemedicineHumansTestosteroneOrthopedics and Sports MedicineMuscle SkeletalTestosteroneAgedNutrition and DieteticsbiologyDehydroepiandrosterone Sulfatebusiness.industryGeneral MedicineMiddle AgedDietary FatsHormonesNutritional counselingEndocrinologyBody Compositionbiology.proteinFemaleDietary ProteinsEnergy IntakebusinessMuscle ContractionRecommended IntakeHormone
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Changes in muscle morphology, electromyographic activity, and force production characteristics during progressive strength training in young and olde…

1998

Effects of a 10-week progressive strength training program composed of a mixture of exercises for increasing muscle mass, maximal peak force, and explosive strength (rapid force production) were examined in 8 young (YM) (29+/-5 yrs) and 10 old (OM) (61+/-4 yrs) men. Electromyographic activity, maximal bilateral isometric peak force, and maximal rate of force development (RFD) of the knee extensors, muscle cross-sectional area (CSA) of the quadriceps femoris (QF), muscle fiber proportion, and fiber areas of types I, IIa, IIb, and IIab of the vastus lateralis were evaluated. Maximal and explosive strength values remained unaltered in both groups during a 3-week control period with no training…

AdultMalemedicine.medical_specialtyAgingVastus lateralis muscleStrength trainingMuscle Fibers SkeletalElectromyographyIsometric exerciseMuscle massMuscle hypertrophyMuscle morphologyInternal medicineMedicineHumansKneeMuscle SkeletalPhysical Education and Trainingmedicine.diagnostic_testbusiness.industryElectromyographySkeletal muscleAnatomyMiddle AgedEndocrinologymedicine.anatomical_structureGeriatrics and GerontologybusinessThe journals of gerontology. Series A, Biological sciences and medical sciences
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The effects of creatine supplementation on muscular performance and body composition responses to short-term resistance training overreaching

2003

To determine the effects of creatine supplementation during short-term resistance training overreaching on performance, body composition, and resting hormone concentrations, 17 men were randomly assigned to supplement with 0.3 g/kg per day of creatine monohydrate (CrM: n=9) or placebo (P: n=8) while performing resistance exercise (5 days/week for 4 weeks) followed by a 2-week taper phase. Maximal squat and bench press and explosive power in the bench press were reduced during the initial weeks of training in P but not CrM. Explosive power in the bench press, body mass, and lean body mass (LBM) in the legs were augmented to a greater extent in CrM ( P<or=0.05) by the end of the 6-week period…

AdultMalemedicine.medical_specialtyPhysiologyStrength trainingAdministration OralBlood PressureCreatineBench presschemistry.chemical_compoundHeart RatePhysiology (medical)Internal medicinemedicineHumansOrthopedics and Sports MedicineMuscle SkeletalPhysical Education and Trainingbusiness.industryOvertrainingFree androgen indexPublic Health Environmental and Occupational HealthGeneral MedicineCreatineOverreachingmedicine.diseaseAdaptation PhysiologicalHormonesEndocrinologychemistryDietary SupplementsBody CompositionPhysical EnduranceLean body massCreatine MonohydratebusinessPsychomotor PerformanceMuscle ContractionEuropean Journal of Applied Physiology
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Endocrine Response Patterns to Acute Unilateral and Bilateral Resistance Exercise in Men

2009

Rehabilitation programs and research experiments use single-arm protocols in which the contralateral arm is not functional or used as a control limb. This study was interested in determining the hormonal signal impacts of such one- versus two-arm exercise responses that might have an impact on adaptational changes with training. The purpose was to examine the acute hormonal responses to a unilateral and a bilateral upper-body resistance exercise (RE) protocol. A balanced randomized treatment intervention with series time frame for blood collections before and after exercise was used as the basic experimental design. Ten recreationally resistance trained men (18-25 years, 20.4 +/- 1.2 years,…

AdultMalemedicine.medical_specialtyAdolescentHydrocortisonemedicine.medical_treatmentPhysical ExertionPhysical Therapy Sports Therapy and RehabilitationHematocritlaw.inventionHemoglobinsYoung AdultRandomized controlled triallawInternal medicinemedicineHumansInsulinEndocrine systemTestosteroneOrthopedics and Sports MedicineYoung adultTestosteroneRehabilitationmedicine.diagnostic_testHuman Growth HormoneInsulinResistance TrainingGeneral MedicineEndocrinologyHematocritAnesthesiaArmLactatesPsychologyHormoneJournal of Strength and Conditioning Research
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Recovery from a national collegiate athletic association division I football game: muscle damage and hormonal status.

2008

The purpose of this study was to examine markers of skeletal muscle tissue damage and circulating anabolic and catabolic hormones to gain insight into the recovery process from Friday until Monday, when a new practice week begins. Twenty-eight National Collegiate Athletic Association Division I football players gave consent to participate in the investigation in the ninth game of the season. Sixteen players started the game and played the entire game (PL), and 12 others did not play and were on the bench during the game (DNP). Each player had fasted blood samples obtained at the same time of day between 1000 and 1200 hours the day before the game (Friday; T1), 18-20 hours after the game (Su…

Malemedicine.medical_specialtyTime FactorsAnabolismHydrocortisoneUniversitiesFootballAmerican footballPhysiologyPhysical Therapy Sports Therapy and RehabilitationEndocrine SystemFootballAthletic PerformanceRisk AssessmentCohort StudiesYoung AdultmedicineHumansOrthopedics and Sports MedicineTestosteroneMuscle SkeletalCreatine KinaseTestosteronebiologyL-Lactate DehydrogenaseCatabolismbusiness.industryMyoglobinGeneral MedicineRecovery of Functionmedicine.diseaseSoft tissue injuryMuscle FatiguePhysical therapybiology.proteinCreatine kinasebusinesshuman activitiesBlood Chemical AnalysisHormoneJournal of strength and conditioning research
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Protein Ingestion Prior to Strength Exercise Affects Blood Hormones and Metabolism

2005

HULMI, J. J., J. S. VOLEK, H. SELANNE, and A. A. MERO. Protein Ingestion Prior to Strength Exercise Affects Blood Hormones and Metabolism. Med. Sci. Sports Exerc., Vol. 37, No. 11, pp. 1990 -1997, 2005. Purpose: The effects of protein consumption before strength training session on blood hormones, energy metabolites, RER, and excess postexercise oxygen consumption (EPOC) were examined. Methods: Ten resistance-trained young men consumed either a 25 g of whey and caseinate proteins (PROT) or a noncaloric placebo (P) in a liquid form 30 min before a heavy strength training session (STS) in a crossover design separated by at least 7 d. STS lasted 50 min and included 5 1 RM squats, 3 10 RM squat…

AdultMalemedicine.medical_specialtyTime FactorsWeight LiftingStrength trainingmedicine.medical_treatmentPhysical Therapy Sports Therapy and RehabilitationPhysical exercisePlacebosOxygen ConsumptionInternal medicinemedicineHumansInsulinIngestionTestosteroneOrthopedics and Sports MedicinePancreatic hormoneCross-Over StudiesHuman Growth HormoneChemistryInsulinFatty AcidsVenous bloodMilk ProteinsCrossover studyWhey ProteinsEndocrinologyArea Under CurveDietary ProteinsOxidation-ReductionHormoneMedicine &amp; Science in Sports &amp; Exercise
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Effect of circulating growth hormone on muscle IGF-I protein concentration in female mice with growth hormone receptor gene disruption.

2009

Growth hormone (GH) is a potent secretague for circulating insulin-like growth factor-I (IGF-I). The purpose of this study was to examine the effect of circulating GH on muscle IGF-I protein expression using GH transgenic animal models. Three different models were used: mice that overexpress bovine GH (bGH; n=10), mice without a functional GH receptor (GHR-/-; n=10), and wildtype mice (n=10). All mice were 16-week old females and each group differed in their basic phenotypic characteristics. Immediately after euthanization the triceps surae muscle group (soleus, plantaris, and gastrocnemius muscles) was removed. IGF-I was extracted from the muscle with an acid-ethanol solution (12.5% 2N hyd…

Malemedicine.medical_specialtyEndocrinology Diabetes and MetabolismTransgenemedicine.medical_treatmentMice TransgenicGrowth hormone receptorBiologyMiceEndocrinologyTriceps surae muscleInternal medicinemedicineAnimalsInsulin-Like Growth Factor IReceptorMuscle SkeletalInsulin-like growth factor 1 receptorMice KnockoutGrowth factorRadioimmunoassayReceptors SomatotropinMice Inbred C57BLEndocrinologyGrowth HormoneCattleFemaleHormoneGrowth hormoneIGF research : official journal of the Growth Hormone Research Society and the International IGF Research Society
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Effects of heavy-resistance training on hormonal response patterns in younger vs. older men.

1999

To examine the adaptations of the endocrine system to heavy-resistance training in younger vs. older men, two groups of men (30 and 62 yr old) participated in a 10-wk periodized strength-power training program. Blood was obtained before, immediately after, and 5, 15, and 30 min after exercise at rest before and after training and at rest at −3, 0, 6, and 10 wk for analysis of total testosterone, free testosterone, cortisol, growth hormone, lactate, and ACTH analysis. Resting values for insulin-like growth factor (IGF)-I and IGF-binding protein-3 were determined before and after training. A heavy-resistance exercise test was used to evaluate the exercise-induced responses (4 sets of 10-repe…

AdultMalemedicine.medical_specialtyAgingHydrocortisoneWeight LiftingPhysiologyPhysical exerciseSquatAdrenocorticotropic hormoneHematocritAdrenocorticotropic HormonePhysiology (medical)Internal medicinemedicineHumansTestosteroneInsulin-Like Growth Factor IMuscle SkeletalHydrocortisonemedicine.diagnostic_testbusiness.industryHuman Growth HormoneTestosterone (patch)Middle Agedmedicine.diseaseHormonesEndocrinologyInsulin-Like Growth Factor Binding Protein 3HematocritPhysical FitnessSarcopeniaBody CompositionbusinessHormonemedicine.drugJournal of applied physiology (Bethesda, Md. : 1985)
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Acute Effects of High-intensity Resistance Exercise on Cognitive Function

2021

The purpose of the present study was to examine the influence of an acute bout of high-intensity resistance exercise on measures of cognitive function. Ten men (Mean ± SD: age = 24.4 ± 3.2 yrs; body mass = 85.7 ± 11.8 kg; height = 1.78 ± 0.08 m; 1 repetition maximum (1RM) = 139.0 ± 24.1 kg) gave informed consent and performed a high-intensity 6 sets of 10 repetitions of barbell back squat exercise at 80% 1RM with 2 minutes rest between sets. The Automated Neuropsychological Assessment Metrics (ANAM) was completed to assess various cognitive domains during the familiarization period, immediately before, and immediately after the high-intensity resistance exercise bout. The repeated measures …

AdultMaleElementary cognitive taskmedicine.medical_specialtyfyysinen rasitusPhysical Therapy Sports Therapy and RehabilitationSquatAudiologyYoung Adult03 medical and health sciencesCognition0302 clinical medicineHeart RateMemoryexercise stressReaction TimemedicineHumansAttentionOrthopedics and Sports MedicineLactic AcidMuscle StrengthNeuropsychological assessmentback squatmedicine.diagnostic_testMuscle fatiguebusiness.industryResistance trainingRepeated measures designliikuntafysiologiaResistance TrainingCognition030229 sport scienceskognitiiviset prosessitreaktiotautomated neuropsychological assessment metricsMental RecallGV557-1198.995Sports medicinemuscle fatiguevoimaharjoitteluAnalysis of variancebusinessRC1200-1245030217 neurology & neurosurgeryResearch ArticleSportsJournal of Sports Science and Medicine
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Differential effects of exhaustive cycle ergometry on concentric and eccentric torque production.

2001

The purpose of this study was to investigate the potential differences in peak isokinetic concentric end eccentric torque following low- and high-intensity cycle exercise fatigue protocols. Ten healthy, recreationally-active men were tested in a balanced, randomized testing sequence for peak eccentric and concentric isokinetic torque (60 degrees/sec) immediately before and after three experimental conditions each separated by 48 hours: 1) a bout of high intensity cycling consisting of a maximal 90-second sprint; 2) a bout of low-intensity cycling at 60 rpm equated for total work with the high-intensity protocol: and 3) no exercise (control bout). Blood was drawn from an antecubital vein and…

AdultMalemedicine.medical_specialtyPhysical Therapy Sports Therapy and RehabilitationConcentricInternal medicinemedicineEccentricTorqueHumansOrthopedics and Sports MedicineKneeLactic AcidExercise physiologyMuscle SkeletalExerciseCross-Over StudiesPhysical Education and TrainingChemistryCrossover studyDifferential effectsSprintTorqueMuscle FatiguePhysical therapyCardiologyExercise Testhuman activitiesCycle ergometryMuscle ContractionJournal of science and medicine in sport
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Effects of Strength Training and Nutritional Counseling on Metabolic Health Indicators in Aging Women

2005

Purpose: Effects of strength training (ST) and nutritional counseling (NC) on metabolic health indicators were examined in 50 aging women. Methods: Subjects performed ST for 21 weeks. NC was given to obtain sufficient energy and protein intake, and recommended intake of fat and fiber. Results: NC increased intake of protein and polyunsaturated fat by 4.5% and 10.7% and decreased intake of saturated fat by 18.3%. Serum concentrations of total cholesterol (TC), LDL-cholesterol (LDL-C), total and HDL-cholesterol (HDL-C) ratio and triacylglycerols (TAG) decreased, and serum HDL-C increased in all subjects after ST. Respectively, systolic and diastolic blood pressure and serum insulin concentrat…

Counselingmedicine.medical_specialtyPhysiologyStrength trainingSaturated fatBlood PressurePhysical exerciseBody Mass IndexPolyunsaturated fatHeart RateDiabetes mellitusInternal medicineHumansMedicineNutritional Physiological PhenomenaOrthopedics and Sports MedicineMuscle SkeletalExerciseTriglyceridesAgedbusiness.industryCholesterol HDLCholesterol LDLMiddle Agedmedicine.diseaseCholesterolBlood pressureEndocrinologyAgeingBody CompositionFemalelipids (amino acids peptides and proteins)businessLipoproteinCanadian Journal of Applied Physiology
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Relationship between off-ice testing variables and on-ice speed in women's collegiate synchronized figure skaters: implications for training.

2010

The purpose of the current investigation was to identify any existing relationships between off-ice performance measures and on-ice performance quantified by speed and acceleration. Twenty-seven women (age 19 +/- 1 year; body mass (59.5 +/- 6.8 kg; height 164.6 +/- 6.35 cm; body fat 23.2 +/- 3.9%) who were collegiate synchronized figure skaters volunteered for the investigation. To examine the relationship between off-ice performance and on-ice speed and acceleration, collegiate synchronized skaters were evaluated on various performance tests over a 1-week period. Off-ice tests completed were peak torque for hip abduction and adduction, 40-yard sprint, vertical jump height, 30-second slide …

Training (meteorology)STRIDEPhysical Therapy Sports Therapy and RehabilitationSquatGeneral MedicineAthletic PerformanceBody Mass IndexAccelerationVertical jumpYoung AdultSprintSkatingDashStatisticsExercise TestPlyometricsHumansOrthopedics and Sports MedicineFemaleExerciseMathematicsJournal of strength and conditioning research
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Effects of L-Carnitine L-Tartrate Supplementation on Muscle Oxygenation Responses to Resistance Exercise

2008

Previous research has shown that L-carnitine L-tartrate (LCLT) supplementation beneficially affects markers of hypoxic stress following resistance exercise. However, the mechanism of this response is unclear. Therefore, the primary purpose of this study was to determine the effects of LCLT supplementation on muscle tissue oxygenation during and after multiple sets of squat exercise. Nine healthy, previously resistance-trained men (25.2 +/- 6.years, 91.2 +/- 10.2 kg, 180.2 +/- 6.3 cm) ingested 2 g.d of LCLT or an identical placebo for 23 days in a randomized, balanced, crossover, double-blind, placebo-controlled, repeated-measures study design. On day 21, forearm muscle oxygenation was measu…

AdultMaleMuscle tissuemedicine.medical_specialtyPhysical Therapy Sports Therapy and RehabilitationProstacyclinPlaceboOxygen ConsumptionDouble-Blind MethodForearmCarnitineMalondialdehydeInternal medicinemedicineHumansOrthopedics and Sports MedicineMuscle SkeletalExerciseTartratesL-Carnitine L-TartrateCross-Over StudiesSpectroscopy Near-Infraredbusiness.industryGeneral MedicineOxygenationCrossover studySurgeryOxygenmedicine.anatomical_structureDietary SupplementsVitamin B ComplexCardiologybusinessmedicine.drugBlood drawingJournal of Strength and Conditioning Research
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Effects of amino acids supplement on physiological adaptations to resistance training.

2009

KRAEMER, W. J., D. L. HATFIELD, J. S. VOLEK, M. S. FRAGALA, J. L. VINGREN, J. M. ANDERSON, B. A. SPIERING, G. A. THOMAS, J. Y. HO, E. E. QUANN, M. IZQUIERDO, K. HAKKINEN, and C. M. MARESH. Effects of Amino Acids Supplement on Physiological Adaptations to Resistance Training. Med. Sci. Sports Exerc., Vol. 41, No. 5, pp. 1111-1121, 2009. Introduction: Previous research has demonstrated that ingestion of essential amino acids and their metabolites induce anabolic effects with the potential to augment gains in lean body mass and strength after resistance exercise training. Purpose: The purpose of the present study was to examine the effects of an essential amino acid-based formula (Muscle Armor…

AdultMalemedicine.medical_specialtyAnabolismPhysical Therapy Sports Therapy and RehabilitationYoung AdultDouble-Blind MethodInternal medicinemedicineIngestionHumansOrthopedics and Sports MedicineMuscle StrengthAmino AcidsTestosteroneHydrocortisonebiologybusiness.industrySkeletal muscleResistance TrainingAdaptation PhysiologicalEndocrinologymedicine.anatomical_structureDietary SupplementsLean body massbiology.proteinCreatine kinasebusinessmedicine.drugBlood drawingMedicine and science in sports and exercise
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Influence of exercise training on physiological and performance changes with weight loss in men.

1999

The purpose of this study was to examine the physiological effects of a weight-loss dietary regimen with or without exercise.Thirty-five overweight men were matched and randomly placed into either a control group (C; N = 6) or one of three dietary groups; a diet-only group (D; N = 8), a diet group that performed aerobic exercise three times per week (DE; N = 11); and a diet group that performed both aerobic and strength training three times per week (DES; N = 10).After 12 wk, D, DE, and DES demonstrated a similar and significant (Por = 0.05) reduction in body mass (-9.64, -8.99, and -9.90 kg, respectively) with fat mass comprising 69, 78, and 97% of the total loss in body mass, respectively…

AdultMalemedicine.medical_specialtyDiet ReducingPhysical Therapy Sports Therapy and RehabilitationPhysical exerciselaw.inventionBody Mass IndexOxygen ConsumptionRandomized controlled triallawWeight lossWeight LossMedicineHumansOrthopedics and Sports MedicineObesityExercise physiologyExerciseAnalysis of Variancebusiness.industrymedicine.diseaseObesityLipidsPhysical therapyBody CompositionRegression AnalysisAnalysis of variancemedicine.symptombusinessDietary regimenBody mass indexMedicine and science in sports and exercise
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Glucocorticoid receptor expression on human B cells in response to acute heavy resistance exercise.

2011

&lt;i&gt;Objective:&lt;/i&gt; To examine glucocorticoid receptor (GCR) expression on B lymphocytes in response to an acute bout of resistance exercise. &lt;i&gt;Methods:&lt;/i&gt; Using a within-subject design, resistance-trained women (n = 7; age: 22.13 ± 3.09 years; height: 1.69 ± 0.084 m; body weight: 65.60 ± 10.01 kg; body mass index: 22.63 ± 2.03 kg/m&lt;sup&gt;2&lt;/sup&gt;; means ± SD) and men (n = 8; age: 23.28 ± 4.26 years; height: 1.73 ± 0.086 m; body weight: 73.93 ± 12.71 kg; body mass index: 24.51 ± 2.61 kg/m&lt;sup&gt;2&lt;/sup&gt;; means ± SD) performed an acute resistance exercise protocol (6 sets of 5 repetition maximum heavy squats) and a control test in a balanced, randomi…

AdultMalemedicine.medical_specialtyHydrocortisoneImmunologyPhysical ExertionB-Lymphocyte SubsetsPhysical Therapy Sports Therapy and RehabilitationBiologyYoung AdultEndocrinologyImmune systemGlucocorticoid receptorReceptors GlucocorticoidInternal medicineImmune ToleranceEndocrine systemMedicineHumansOrthopedics and Sports MedicineEndocrine and Autonomic SystemsAdrenal cortexbusiness.industryResistance trainingGeneral Medicinemedicine.anatomical_structureEndocrinologyNeurologyPhysical FitnessImmunologyFemalebusinesshuman activitiesNeuroimmunomodulation
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Hormonal stress responses of growth hormone and insulin-like growth factor-I in highly resistance trained women and men

2021

Abstract The purpose of this study was to examine the responses of growth hormone (GH) and insulin-like growth factor-I (IGF I) to intense heavy resistance exercise in highly trained men and women to determine what sex-dependent responses may exist. Subjects were highly resistance trained men (N = 8, Mean ± SD; age, yrs., 21 ± 1, height, cm, 175.3 ± 6.7, body mass, kg, 87.0 ± 18.5, % body fat, 15.2 ± 5.4, squat X body mass, 2.1 ± 0.4; and women (N = 7; Mean ± SD, age, yrs. 24 ± 5, height, cm 164.6 ± 6.7, body mass, kg 76.4 ± 8.8, % body fat, 26.9 ± 5.3, squat X body mass, 1.7 ± 0.6). An acute resistance exercise test protocol (ARET) consisted of 6 sets of 10 repetitions at 80% of the 1 RM w…

AdultMale0301 basic medicinemedicine.medical_specialtyAnabolismEndocrinology Diabetes and Metabolismmedicine.medical_treatment030209 endocrinology & metabolismSquatGrowth hormone03 medical and health sciencesInsulin-like growth factorSex Factors0302 clinical medicineEndocrinologyStress PhysiologicalInternal medicineHumansMedicineInsulin-Like Growth Factor IHuman Growth Hormonebusiness.industryInsulinGrowth factorResistance TrainingPrognosisSexual dimorphism030104 developmental biologyEndocrinologyFemalebusinessBiomarkersFollow-Up StudiesHormoneGrowth Hormone &amp; IGF Research
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Effect of resistance exercise on muscle steroid receptor protein content in strength-trained men and women

2009

The purpose of this study was to examine the acute effect of resistance exercise (RE) on muscle androgen receptor (AR) and glucocorticoid receptor (GR) protein content. Fifteen resistance-trained men (n=8; 21+/-1 years, 175.3+/-6.7 cm, 90.8+/-11.6 kg) and women (n=7; 24+/-5 years, 164.6+/-6.7 cm, 76.4+/-15.6 kg) completed 6 sets of 10 repetitions of heavy squats. Blood samples were obtained before RE, after 3 and 6 sets of squats, and 5, 15, 30 and 70 min after RE. Muscle biopsies from the vastus lateralis were obtained before RE, and 10 min and 70 min after RE. Blood samples were analyzed for total and free testosterone concentrations and muscle samples were analyzed for AR and GR protein …

AdultMalemedicine.medical_specialtymedicine.drug_classmedicine.medical_treatmentClinical BiochemistryPhysical exerciseBiologyBiochemistrySteroidYoung AdultReceptors GlucocorticoidSex FactorsEndocrinologyGlucocorticoid receptorInternal medicinemedicineHumansTestosteroneMuscle SkeletalReceptorExerciseMolecular BiologyTestosteronePharmacologyOrganic ChemistryResistance trainingResistance TrainingAndrogenAndrogen receptorEndocrinologyReceptors AndrogenFemaleSteroids
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Effect of alkalosis on plasma epinephrine responses to high intensity cycle exercise in humans

2002

The purpose of this study was to determine the effects of alkalosis on epinephrine concentrations in response to a 90 s maximal exercise test. A group of ten healthy men ingested either a bicarbonate (BS) supplement (0.3 g x kg(-1) of body mass of sodium bicarbonate) or placebo mixture (P) prior to performing a 90 s maximal cycle ergometer test. An indwelling Teflon cannula was placed in the antecubital vein and blood samples were drawn at three times at rest separated by 10 min, immediately following the protocol, and at 2.5, 5, and 10 min post exercise to determine plasma epinephrine concentrations. Sodium bicarbonate ingestion significantly ( P0.05) induced alkalosis both at rest [mean (…

Adultmedicine.medical_specialtyAlkalosisEpinephrineBicarbonatePlacebochemistry.chemical_compoundPhysiology (medical)Internal medicineBlood plasmamedicineHumansIngestionOrthopedics and Sports MedicineLactic AcidChildAcid-Base EquilibriumSodium bicarbonatebusiness.industryPublic Health Environmental and Occupational HealthAlkalosisGeneral MedicineHydrogen-Ion Concentrationmedicine.diseaseBicyclingBicarbonatesEpinephrineEndocrinologychemistryPhysical EnduranceCatecholaminebusinessmedicine.drugEuropean Journal of Applied Physiology
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Epinephrine Preworkout Elevation May Offset Early Morning Melatonin Concentrations to Maintain Maximal Muscular Force and Power in Track Athletes

2014

The optimal time of day for training has become an important question for many strength and conditioning specialists, and this study was designed to add some insights into this complex question. The primary purpose of this investigation was to examine physical performance within the temporal context of the relationship between physical performance, epinephrine, and melatonin concentrations in the early morning (0530 hours) and late (1500 hours) afternoon in elite collegiate male track and field athletes (jumpers and sprinters). Subjects had a mean (±SD) age, height, and body mass of 20.4 (±1.6) years, 185.8 (±9.4) cm, and 77.9 (±8.5) kg, respectively. Blood was obtained before each AM and P…

Malemedicine.medical_specialtyTime FactorsAdolescentEpinephrineAdrenergicPhysical Therapy Sports Therapy and RehabilitationAthletic PerformanceRunningArousalMelatoninYoung AdultVertical jumpPineal glandInternal medicinemedicineHumansOrthopedics and Sports MedicineMuscle Strengthta315Muscle SkeletalExerciseMelatoninMorningCross-Over StudiesbiologyAthletesTrack and FieldGeneral Medicinebiology.organism_classificationEndocrinologymedicine.anatomical_structureEpinephrineCardiologyPsychologyPhysical Conditioning Humanmedicine.drugJournal of Strength and Conditioning Research
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l-Carnitine l-tartrate supplementation favorably affects biochemical markers of recovery from physical exertion in middle-aged men and women.

2009

The purpose of this study was to examine the effects of Carnipure tartrate (Lonza, Allendale, NJ) supplementation (total dose of 2 g/d of l-carnitine) on markers of performance and recovery from physical exertion in middle-aged men and women. Normally active and healthy men (n = 9, 45.4 +/- 5.3 years old) and women (n = 9, 51.9 +/- 5.0 years old) volunteered to participate in the investigation. Double-blind, placebo, balanced treatment presentation and crossover design were used with 3 weeks and 3 days of supplementation followed by a 1-week washout period before the other counterbalanced treatment was initiated. After 3 weeks of each supplementation protocol, each participant then performe…

Muscle tissueAdultMalemedicine.medical_specialtyXanthine OxidaseFree RadicalsEndocrinology Diabetes and MetabolismPhysical ExertionPlaceboEndocrinologyDouble-Blind MethodInternal medicineCarnitinemedicineHumansCarnitineExertionLactic AcidLeg pressTartratesCross-Over Studiesbiologybusiness.industryMyoglobinMiddle AgedCrossover studyMiddle agemedicine.anatomical_structureEndocrinologyPurinesDietary Supplementsbiology.proteinCreatine kinaseFemalebusinessBiomarkersmedicine.drugMetabolism: clinical and experimental
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The effects of short-term resistance training on endocrine function in men and women.

1998

This investigation examined hormonal adaptations to acute resistance exercise and determined whether training adaptations are observed within an 8-week period in untrained men and women. The protocol consisted of a 1-week pre-conditioning orientation phase followed by 8 weeks of heavy resistance training. Three lower-limb exercises for the quadriceps femoris muscle group (squat, leg press, knee extension) were performed twice a week (Monday and Friday) with every other Wednesday used for maximal dynamic 1 RM strength testing. Blood samples were obtained pre-exercise (Pre-Ex), immediately post-exercise (IP), and 5 min post-exercise (5-P) during the first week of training (T-1), after 6 weeks…

AdultMalemedicine.medical_specialtyTime FactorsPhysiologymedicine.drug_classSquatSex hormone-binding globulinPhysiology (medical)Internal medicineSex Hormone-Binding GlobulinmedicineHumansOrthopedics and Sports MedicineTestosteroneLactic AcidExercise physiologyLeg pressExerciseTestosteroneHydrocortisoneSex Characteristicsbiologybusiness.industryHuman Growth HormonePublic Health Environmental and Occupational HealthGeneral MedicineAndrogenQuadriceps femoris muscleHormonesCortisoneEndocrinologybiology.proteinFemalebusinessmedicine.drugEuropean journal of applied physiology and occupational physiology
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LONGITUDINAL TRACKING OF MUSCULAR POWER CHANGES OF NCAA DIVISION I COLLEGIATE WOMEN GYMNASTS

2004

Gymnastics relies upon power as a critical component of sports-specific fitness. The purpose of this study was to monitor long-term training adaptations in the power of National Collegiate Athletics Association Division I women gymnasts. Twenty members of a women's gymnastic team (aged 18-22) were tracked over 3 years with the first year a baseline year of testing. Whole body power for the counter-movement (CMJ) and squat (SJ) vertical jump was obtained via force plate analyses at 2 assessment time points during each year (February and November). Results showed significant (p < or = 0.05) and continued increases in peak power output in the CMJ and SJ at each biannual assessment. Improvement…

medicine.medical_specialtybusiness.industryPeak power outputSquatPhysical Therapy Sports Therapy and RehabilitationGeneral MedicineMuscular powerMuscle massVertical jumpFat free massPhysical therapymedicineTime to peakOrthopedics and Sports MedicineExercise physiologybusinessJournal of Strength and Conditioning Research
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Endogenous opioid peptide responses to opioid and anti-inflammatory medications following eccentric exercise-induced muscle damage.

2009

To determine the effects of Vicoprofen, Ibuprofen, and a placebo on the responses of endogenous opioid peptides following eccentric exercise-induced muscle damage 36 healthy men (age: 22.8 years; height: 178.8+/-6.2cm; body mass: 78.9+/-13.7kg; body fat: 15.8+/-6.5%) volunteered to participate in the study. Each participant was evaluated for pain 24h post and randomly assigned to an experimental group: VIC (Vicoprofen), IBU (Ibuprofen), or P (placebo). Medication was given four times daily (i.e., VIC (hydrocodone bitartrate 7.5mg with Ibuprofen 200mg) and IBU 200mg). Blood was obtained at rest and at 0, 24, 48, 72, 96 and 120h following the eccentric exercise damage protocol. No significant…

AdultMalemedicine.medical_specialtyAdolescentPhysiologyPhysical ExertionAnti-Inflammatory AgentsPainPhysical exercisePlaceboBiochemistryPlacebosCellular and Molecular NeuroscienceYoung AdultEndocrinologyDouble-Blind MethodInternal medicinemedicineEccentricAnimalsHumansOpioid peptideMuscle SkeletalExerciseEndogenous opioidPain MeasurementChemistryIbuprofenMagnetic Resonance ImagingEndocrinologymedicine.anatomical_structureOpioidOpioid PeptidesAdrenal medullamedicine.drugPeptides
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