Molecular, Genetic, and Biochemical Nutrition Commons^™

The Effects Of Phosphocreatine Disodium Salts Plus Blueberry Extract Supplementation On Muscular Strength, Power, And Endurance, John Paul V. Anders, Tyler J. Neltner, Robert W. Smith, Joshua L. Keller, Terry J. Housh, F Joseph Daugherty, Michael S. Tempesta, Alekha K. Dash, Daniel J. Munt, Richard J. Schmidt, Glen O. Johnson

Department of Nutrition and Health Sciences: Faculty Publications

Background: Numerous studies have demonstrated the efficacy of creatine supplementation for improvements in exercise performance. Few studies, however, have examined the effects of phosphocreatine supplementation on exercise performance. Furthermore, while polyphenols have antioxidant and anti-inflammatory properties, little is known regarding the influence of polyphenol supplementation on muscular strength, power, and endurance. Thus, the purpose of the present study was to compare the effects of 28 days of supplementation with phosphocreatine disodium salts plus blueberry extract (PCDSB), creatine monohydrate (CM), and placebo on measures of muscular strength, power, and endurance.

Methods: Thirty-three men were randomly assigned to consume either PCDSB, CM, …

Co-Activation, Estimated Anterior And Posterior Cruciate Ligament Forces, And Motor Unit Activation Strategies During The Time Course Of Fatigue, Cory M. Smith, Terry J. Housh, Ethan C. Hill, Josh L. Keller, Glen O. Johnson, Richard J. Schmidt

Department of Nutrition and Health Sciences: Faculty Publications

This study aimed to combine co-activation as well as anterior and posterior cruciate ligament force estimations with the motor unit activation strategies employed by the primary muscles that are involved in the movement at the knee joint. Fourteen male subject performed 25 maximal concentric isokinetic leg extension muscle actions at 120 s^-1. Electromyographic and mechanomyographic signals from the vastus lateralis and bicep femoris, as well as force, were used to measure co-activation, and estimated anterior and posterior ligament forces during the time course of fatigue. There were decreases in quadriceps force and increases in hamstring force during the …

Sex- And Mode-Specific Responses To Eccentric Muscle Fatigue, Ethan C. Hill, Terry J. Housh, Cory M. Smith, Josh L. Keller, Richard J. Schmidt, Glen O. Johnson

Department of Nutrition and Health Sciences: Faculty Publications

The primary purpose of the present investigation was to examine sex-related differences as a result of fatiguing eccentric muscle actions on torque, muscle blood flow, electromyography, and mechanomyography. Eighteen men and 18 women performed peak torque trials prior to (pretest), immediately after (posttest), and 5-min after (recovery) completing 50 submaximal (60 % of eccentric peak torque), eccentric, isokinetic (180 ° · s ⁻ 1) muscle actions of the elbow flexors. Electromyographic and mechanomyographic responses were simultaneously recorded from the biceps brachii muscle, and muscle blood flow was measured at pretest, posttest and recovery. There were sex- and mode-specific responses for …

Muscle- And Mode-Specific Responses Of The Forearm Flexors To Fatiguing, Concentric Muscle Actions, Ethan C. Hill, Terry J. Housh, Cory M. Smith, Richard Schmidt, Glen O. Johnson

Department of Nutrition and Health Sciences: Faculty Publications

Background: Electromyographic (EMG) and mechanomyographic (MMG) studies of fatigue have generally utilized maximal isometric or dynamic muscle actions, but sport- and work-related activities involve predominately submaximal movements. Therefore, the purpose of the present investigation was to examine the torque, EMG, and MMG responses as a result of submaximal, concentric, isokinetic, forearm flexion muscle actions. Methods: Twelve men performed concentric peak torque (PT) and isometric PT trials before (pretest) and after (posttest) performing 50 submaximal (65% of concentric PT), concentric, isokinetic (60°·s^-1), forearm flexion muscle actions. Surface EMG and MMG signals were simultaneously recorded from the biceps brachii and …

Effect Of Sex On Torque, Recovery, Emg, And Mmg Responses To Fatigue, E.C. Hill, Terry J. Housh, C. M. Smith, Kristen C. Cochrane, N.D.M. Jenkins, Joel T. Cramer, Richard J. Schmidt, G. O. Johnson

Department of Nutrition and Health Sciences: Faculty Publications

The purpose of the present investigation was to examine the effect of sex on maximal voluntary isometric contraction (MVIC) torque and the EMG and MMG responses as a result of fatiguing, intermittent, submaximal (65% of MVIC), isometric elbow flexion muscle contractions. Methods: Eighteen men and women performed MVIC trials before (pretest), after (posttest), and 5-min after (5-min recovery) performing 50 intermittent, submaximal isometric muscle contractions. Surface electromyographic (EMG) and mechanomyographic (MMG) signals were simultaneously recorded from the biceps brachii muscle. Results: As a result of the fatiguing workbout torque decreased similarly from pretest to posttest for both the men (24.0%) …

Effects Of Dynamic Stretching On Strength, Muscle Imbalance, And Muscle Activation, Pablo B. Costa, Trent J. Herda, Ashley A. Herda, Joel T. Cramer

Department of Nutrition and Health Sciences: Faculty Publications

Purpose: This study aimed to examine the acute effects of dynamic stretching on concentric leg extensor and flexor peak torque, eccentric leg flexor peak torque, and the conventional and functional hamstring–quadriceps (H:Q) ratios.

Methods: Twenty-one women (mean ± SD age = 20.6 ± 2.0 yr, body mass = 64.5 ± >.3 kg, height = 164.7 ± 6.5 cm) performed maximal voluntary isokinetic leg extension, flexion, and eccentric hamstring muscle actions at the angular velocities of 60°· s^-1 and 180° · s^-1 before and after a bout of dynamic hamstring and quadriceps stretching as well as a …