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Muscle and intensity based hamstring exercise classification in elite female track and field athletes: implications for exercise selection during rehabilitation.

Tsaklis P, Malliaropoulos N, Mendiguchia J, Korakakis V, Tsapralis K, Pyne D, Malliaras P - Open Access J Sports Med (2015)

Bottom Line: The lunge, dead lift, and kettle swings were low intensity (<50% MVIC) and all showed higher EMG activity for semitendinosus than for biceps femoris.This information enables the clinician, strength and conditioning coach and physiotherapist to better understand intensity- and muscle-specific activation during hamstring muscle rehabilitation.Therefore, these results may help in designing progressive strengthening and rehabilitation and prevention programs.

View Article: PubMed Central - PubMed

Affiliation: Department of Physiotherapy, Laboratory of Biomechanics and Ergonomics, Alexander Technological Educational Institute of Thessaloniki, Thessaloniki, Greece ; Department of Mechanical Engineering, Bioengineering, Massachusetts Institute of Technology, Cambridge, MA, USA.

ABSTRACT

Background: Hamstring injuries are common in many sports, including track and field. Strains occur in different parts of the hamstring muscle but very little is known about whether common hamstring loading exercises specifically load different hamstring components. The purpose of this study was to investigate muscle activation of different components of the hamstring muscle during common hamstring loading exercises.

Methods: Twenty elite female track and field athletes were recruited into this study, which had a single-sample, repeated-measures design. Each athlete performed ten hamstring loading exercises, and an electromyogram (EMG) was recorded from the biceps femoris and semitendinosus components of the hamstring. Hamstring EMG during maximal voluntary isometric contraction (MVIC) was used to normalize the mean data across ten repetitions of each exercise. An electrogoniometer synchronized to the EMG was used to determine whether peak EMG activity occurred during muscle-tendon unit lengthening, shortening, or no change in length. Mean EMG values were compared between the two recording sites for each exercise using the Student's t-test.

Results: The lunge, dead lift, and kettle swings were low intensity (<50% MVIC) and all showed higher EMG activity for semitendinosus than for biceps femoris. Bridge was low but approaching medium intensity, and the TRX, hamstring bridge, and hamstring curl were all medium intensity exercises (≥50% or <80% MVIC). The Nordic, fitball, and slide leg exercises were all high intensity exercises. Only the fitball exercise showed higher EMG activity in the biceps femoris compared with the semitendinosus. Only lunge and kettle swings showed peak EMG in the muscle-tendon unit lengthening phase and both these exercises involved faster speed.

Conclusion: Some exercises selectively activated the lateral and medial distal hamstrings. Low, medium, and high intensity exercises were demonstrated. This information enables the clinician, strength and conditioning coach and physiotherapist to better understand intensity- and muscle-specific activation during hamstring muscle rehabilitation. Therefore, these results may help in designing progressive strengthening and rehabilitation and prevention programs.

No MeSH data available.


Related in: MedlinePlus

Kettle bell swing exercise.
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f3-oajsm-6-209: Kettle bell swing exercise.

Mentions: A 12 kg kettle bell is used depending on ability and comfort (Figure 3). The participant bends forward to grip the kettle bell on the ground with both hands. The upper body at this point is parallel to the floor with the knees slightly flexed (approximately 10°–15°). The participant is required to swing the kettle bell back between her legs forcefully then quickly reverse the direction with an explosive extension of the hips while swinging the kettle bell out to chest level; at this time, the hips and knees are extended with the participant standing upright. This is a closed kinematic chain hip dominant exercise.


Muscle and intensity based hamstring exercise classification in elite female track and field athletes: implications for exercise selection during rehabilitation.

Tsaklis P, Malliaropoulos N, Mendiguchia J, Korakakis V, Tsapralis K, Pyne D, Malliaras P - Open Access J Sports Med (2015)

Kettle bell swing exercise.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4492645&req=5

f3-oajsm-6-209: Kettle bell swing exercise.
Mentions: A 12 kg kettle bell is used depending on ability and comfort (Figure 3). The participant bends forward to grip the kettle bell on the ground with both hands. The upper body at this point is parallel to the floor with the knees slightly flexed (approximately 10°–15°). The participant is required to swing the kettle bell back between her legs forcefully then quickly reverse the direction with an explosive extension of the hips while swinging the kettle bell out to chest level; at this time, the hips and knees are extended with the participant standing upright. This is a closed kinematic chain hip dominant exercise.

Bottom Line: The lunge, dead lift, and kettle swings were low intensity (<50% MVIC) and all showed higher EMG activity for semitendinosus than for biceps femoris.This information enables the clinician, strength and conditioning coach and physiotherapist to better understand intensity- and muscle-specific activation during hamstring muscle rehabilitation.Therefore, these results may help in designing progressive strengthening and rehabilitation and prevention programs.

View Article: PubMed Central - PubMed

Affiliation: Department of Physiotherapy, Laboratory of Biomechanics and Ergonomics, Alexander Technological Educational Institute of Thessaloniki, Thessaloniki, Greece ; Department of Mechanical Engineering, Bioengineering, Massachusetts Institute of Technology, Cambridge, MA, USA.

ABSTRACT

Background: Hamstring injuries are common in many sports, including track and field. Strains occur in different parts of the hamstring muscle but very little is known about whether common hamstring loading exercises specifically load different hamstring components. The purpose of this study was to investigate muscle activation of different components of the hamstring muscle during common hamstring loading exercises.

Methods: Twenty elite female track and field athletes were recruited into this study, which had a single-sample, repeated-measures design. Each athlete performed ten hamstring loading exercises, and an electromyogram (EMG) was recorded from the biceps femoris and semitendinosus components of the hamstring. Hamstring EMG during maximal voluntary isometric contraction (MVIC) was used to normalize the mean data across ten repetitions of each exercise. An electrogoniometer synchronized to the EMG was used to determine whether peak EMG activity occurred during muscle-tendon unit lengthening, shortening, or no change in length. Mean EMG values were compared between the two recording sites for each exercise using the Student's t-test.

Results: The lunge, dead lift, and kettle swings were low intensity (<50% MVIC) and all showed higher EMG activity for semitendinosus than for biceps femoris. Bridge was low but approaching medium intensity, and the TRX, hamstring bridge, and hamstring curl were all medium intensity exercises (≥50% or <80% MVIC). The Nordic, fitball, and slide leg exercises were all high intensity exercises. Only the fitball exercise showed higher EMG activity in the biceps femoris compared with the semitendinosus. Only lunge and kettle swings showed peak EMG in the muscle-tendon unit lengthening phase and both these exercises involved faster speed.

Conclusion: Some exercises selectively activated the lateral and medial distal hamstrings. Low, medium, and high intensity exercises were demonstrated. This information enables the clinician, strength and conditioning coach and physiotherapist to better understand intensity- and muscle-specific activation during hamstring muscle rehabilitation. Therefore, these results may help in designing progressive strengthening and rehabilitation and prevention programs.

No MeSH data available.


Related in: MedlinePlus