Effects of load on good morning kinematics and EMG activity

Many strength and conditioning coaches utilize the good morning (GM) to strengthen the hamstrings and spinal erectors. However, little research exists on its electromyography (EMG) activity and kinematics, and how these variables change as a function of load. The purpose of this investigation was to...

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Main Authors: Andrew David Vigotsky, Erin Nicole Harper, David Russell Ryan, Bret Contreras
Format: Article
Language:English
Published: PeerJ Inc. 2015-01-01
Series:PeerJ
Subjects:
Online Access:https://peerj.com/articles/708.pdf
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author Andrew David Vigotsky
Erin Nicole Harper
David Russell Ryan
Bret Contreras
author_facet Andrew David Vigotsky
Erin Nicole Harper
David Russell Ryan
Bret Contreras
author_sort Andrew David Vigotsky
collection DOAJ
description Many strength and conditioning coaches utilize the good morning (GM) to strengthen the hamstrings and spinal erectors. However, little research exists on its electromyography (EMG) activity and kinematics, and how these variables change as a function of load. The purpose of this investigation was to examine how estimated hamstring length, integrated EMG (IEMG) activity of the hamstrings and spinal erectors, and kinematics of the lumbar spine, hip, knee, and ankle are affected by changes in load. Fifteen trained male participants (age = 24.6 ± 5.3 years; body mass = 84.7 ± 11.3 kg; height = 180.9 ± 6.8 cm) were recruited for this study. Participants performed five sets of the GM, utilizing 50, 60, 70, 80, and 90% of one-repetition maximum (1RM) in a randomized fashion. IEMG activity of hamstrings and spinal erectors tended to increase with load. Knee flexion increased with load on all trials. Estimated hamstring length decreased with load. However, lumbar flexion, hip flexion, and plantar flexion experienced no remarkable changes between trials. These data provide insight as to how changing the load of the GM affects EMG activity, kinematic variables, and estimated hamstring length. Implications for hamstring injury prevention are discussed. More research is needed for further insight as to how load affects EMG activity and kinematics of other exercises.
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spelling doaj.art-231ecc4aa2334bcb8f864f1b71d3194d2023-12-03T11:29:53ZengPeerJ Inc.PeerJ2167-83592015-01-013e70810.7717/peerj.708708Effects of load on good morning kinematics and EMG activityAndrew David Vigotsky0Erin Nicole Harper1David Russell Ryan2Bret Contreras3Kinesiology Program, School of Nutrition and Health Promotion, College of Health Solutions, Arizona State University, Phoenix, AZ, USAKinesiology Program, School of Nutrition and Health Promotion, College of Health Solutions, Arizona State University, Phoenix, AZ, USAKinesiology Program, School of Nutrition and Health Promotion, College of Health Solutions, Arizona State University, Phoenix, AZ, USASchool of Sport and Recreation, Auckland University of Technology, Auckland, New ZealandMany strength and conditioning coaches utilize the good morning (GM) to strengthen the hamstrings and spinal erectors. However, little research exists on its electromyography (EMG) activity and kinematics, and how these variables change as a function of load. The purpose of this investigation was to examine how estimated hamstring length, integrated EMG (IEMG) activity of the hamstrings and spinal erectors, and kinematics of the lumbar spine, hip, knee, and ankle are affected by changes in load. Fifteen trained male participants (age = 24.6 ± 5.3 years; body mass = 84.7 ± 11.3 kg; height = 180.9 ± 6.8 cm) were recruited for this study. Participants performed five sets of the GM, utilizing 50, 60, 70, 80, and 90% of one-repetition maximum (1RM) in a randomized fashion. IEMG activity of hamstrings and spinal erectors tended to increase with load. Knee flexion increased with load on all trials. Estimated hamstring length decreased with load. However, lumbar flexion, hip flexion, and plantar flexion experienced no remarkable changes between trials. These data provide insight as to how changing the load of the GM affects EMG activity, kinematic variables, and estimated hamstring length. Implications for hamstring injury prevention are discussed. More research is needed for further insight as to how load affects EMG activity and kinematics of other exercises.https://peerj.com/articles/708.pdfHamstringsInjury preventionHamstring strainHamstring lengthIntensity of load
spellingShingle Andrew David Vigotsky
Erin Nicole Harper
David Russell Ryan
Bret Contreras
Effects of load on good morning kinematics and EMG activity
PeerJ
Hamstrings
Injury prevention
Hamstring strain
Hamstring length
Intensity of load
title Effects of load on good morning kinematics and EMG activity
title_full Effects of load on good morning kinematics and EMG activity
title_fullStr Effects of load on good morning kinematics and EMG activity
title_full_unstemmed Effects of load on good morning kinematics and EMG activity
title_short Effects of load on good morning kinematics and EMG activity
title_sort effects of load on good morning kinematics and emg activity
topic Hamstrings
Injury prevention
Hamstring strain
Hamstring length
Intensity of load
url https://peerj.com/articles/708.pdf
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