Trunk muscle electromyographic activity with unstable and unilateral exercises
- Behm, David, Leonard, Allison, Young, Warren, Bonsey, Andrew, MacKinnon, Scott N.
- Authors: Behm, David , Leonard, Allison , Young, Warren , Bonsey, Andrew , MacKinnon, Scott N.
- Date: 2005
- Type: Text , Journal article
- Relation: Journal of Strength and Conditioning Research Vol. 19, no. 1 (2005), p. 193-201
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- Description: The purpose of this cross-sectional study was to evaluate the effect of unstable and unilateral resistance exercises on trunk muscle activation. Eleven subjects (6 men and 5 women) between 20 and 45 years of age participated. Six trunk exercises, as well as unilateral and bilateral shoulder and chest presses against resistance, were performed on stable (bench) and unstable (Swiss ball) bases. Electromyographic activity of the upper lumbar, lumbosacral erector spinae, and lower-abdominal muscles were monitored. Instability generated greater activation of the lower-abdominal stabilizer musculature (27.9%) with the trunk exercises and all trunk stabilizers (37.7-54.3%) with the chest press. There was no effect of instability on the shoulder press. Unilateral shoulder press produced greater activation of the back stabilizers, and unilateral chest press resulted in higher activation of all trunk stabilizers, when compared with bilateral presses. Regardless of stability, the superman exercise was the most effective trunk-stabilizer exercise for back-stabilizer activation, whereas the side bridge was the optimal exercise for lower-abdominal muscle activation. Thus, the most effective means for trunk strengthening should involve back or abdominal exercises with unstable bases. Furthermore, trunk strengthening can also occur when performing resistance exercises for the limbs, if the exercises are performed unilaterally. © 2005 National Strength & Conditioning Association.
- Description: C1
- Description: 2003001184
- Authors: Behm, David , Leonard, Allison , Young, Warren , Bonsey, Andrew , MacKinnon, Scott N.
- Date: 2005
- Type: Text , Journal article
- Relation: Journal of Strength and Conditioning Research Vol. 19, no. 1 (2005), p. 193-201
- Full Text:
- Reviewed:
- Description: The purpose of this cross-sectional study was to evaluate the effect of unstable and unilateral resistance exercises on trunk muscle activation. Eleven subjects (6 men and 5 women) between 20 and 45 years of age participated. Six trunk exercises, as well as unilateral and bilateral shoulder and chest presses against resistance, were performed on stable (bench) and unstable (Swiss ball) bases. Electromyographic activity of the upper lumbar, lumbosacral erector spinae, and lower-abdominal muscles were monitored. Instability generated greater activation of the lower-abdominal stabilizer musculature (27.9%) with the trunk exercises and all trunk stabilizers (37.7-54.3%) with the chest press. There was no effect of instability on the shoulder press. Unilateral shoulder press produced greater activation of the back stabilizers, and unilateral chest press resulted in higher activation of all trunk stabilizers, when compared with bilateral presses. Regardless of stability, the superman exercise was the most effective trunk-stabilizer exercise for back-stabilizer activation, whereas the side bridge was the optimal exercise for lower-abdominal muscle activation. Thus, the most effective means for trunk strengthening should involve back or abdominal exercises with unstable bases. Furthermore, trunk strengthening can also occur when performing resistance exercises for the limbs, if the exercises are performed unilaterally. © 2005 National Strength & Conditioning Association.
- Description: C1
- Description: 2003001184
Trunk muscle activation during dynamic weight-training exercises and isometric instability activities
- Hamlyn, Nicole, Behm, David, Young, Warren
- Authors: Hamlyn, Nicole , Behm, David , Young, Warren
- Date: 2007
- Type: Text , Journal article
- Relation: Journal of Strength and Conditioning Research Vol. 21, no. 4 (2007), p. 1108-1112
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- Description: The purpose of this study was to examine the extent of activation in various trunk muscles during dynamic weight-training and isometric instability exercises. Sixteen subjects performed squats and deadlifts with 80% 1 repetition maximum (IRM), as well as with body weight as resistance and 2 unstable calisthenic-type exercises (superman and sidebridge). Electromyographic (EMG) activity was measured from the lower abdominals (LA), external obliques (EO), upper lumbar erector spinae (ULES), and lumbar-sacral erector spinae (LSES) muscle groups. Results indicated that the LSES EMG activity during the 80% IRM squat significantly exceeded 80% IRM deadlift LSES EMG activity by 34.5%. The LSES EMG activity of the 80% IRM squat also exceeded the body weight squat, deadlift, superman, and sidebridge by 56, 56.6, 65.5, and 53.1%, respectively. The 80% IRM deadlift ULES EMG activity significantly exceeded the 80% IRM squat exercise by 12.9%. In addition, the 80% IRM deadlift ULES EMG activity also exceeded the body weight squat, deadlift, superman, and sidebridge exercises by 66.7, 65.5, 69.3, and 68.6%, respectively. There were no significant changes in EO or LA activity. Therefore, the augmented activity of the LSES and ULES during 80% IRM squat and deadlift resistance exercises exceeded the activation levels achieved with the same exercises performed with body weight and selected instability exercises. Individuals performing upright, resisted, dynamic exercises can achieve high trunk muscle activation and thus may not need to add instability device exercises to augment core stability training. © 2007 National Strength & Conditioning Association.
- Description: C1
- Description: 2003005669
- Authors: Hamlyn, Nicole , Behm, David , Young, Warren
- Date: 2007
- Type: Text , Journal article
- Relation: Journal of Strength and Conditioning Research Vol. 21, no. 4 (2007), p. 1108-1112
- Full Text:
- Reviewed:
- Description: The purpose of this study was to examine the extent of activation in various trunk muscles during dynamic weight-training and isometric instability exercises. Sixteen subjects performed squats and deadlifts with 80% 1 repetition maximum (IRM), as well as with body weight as resistance and 2 unstable calisthenic-type exercises (superman and sidebridge). Electromyographic (EMG) activity was measured from the lower abdominals (LA), external obliques (EO), upper lumbar erector spinae (ULES), and lumbar-sacral erector spinae (LSES) muscle groups. Results indicated that the LSES EMG activity during the 80% IRM squat significantly exceeded 80% IRM deadlift LSES EMG activity by 34.5%. The LSES EMG activity of the 80% IRM squat also exceeded the body weight squat, deadlift, superman, and sidebridge by 56, 56.6, 65.5, and 53.1%, respectively. The 80% IRM deadlift ULES EMG activity significantly exceeded the 80% IRM squat exercise by 12.9%. In addition, the 80% IRM deadlift ULES EMG activity also exceeded the body weight squat, deadlift, superman, and sidebridge exercises by 66.7, 65.5, 69.3, and 68.6%, respectively. There were no significant changes in EO or LA activity. Therefore, the augmented activity of the LSES and ULES during 80% IRM squat and deadlift resistance exercises exceeded the activation levels achieved with the same exercises performed with body weight and selected instability exercises. Individuals performing upright, resisted, dynamic exercises can achieve high trunk muscle activation and thus may not need to add instability device exercises to augment core stability training. © 2007 National Strength & Conditioning Association.
- Description: C1
- Description: 2003005669
Conflicting effects of fatigue and potentiation on voluntary force
- Behm, David, Button, Duane, Barbour, Glen, Butt, Jeremy, Young, Warren
- Authors: Behm, David , Button, Duane , Barbour, Glen , Butt, Jeremy , Young, Warren
- Date: 2004
- Type: Text , Journal article
- Relation: Journal of Strength and Conditioning Research Vol. 18, no. 2 (2004), p. 365-372
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- Description: The objective of this study was to investigate whether a warm-up consisting of a series of maximal contractions would augment the force and activation of subsequent leg extensor contractions. Both voluntary and evoked isometric contractions were tested to determine the mechanisms underlying the response. Nine subjects were tested for twitch, tetanic, submaximal (30%), and maximal voluntary contractile (MVC) properties before and after (1, 5, 10, and 15 minutes) one to three 10-second MVCs. MVC force either did not change following 1-2 MVCs or was depressed at 10 and 15 minutes after 3 MVCs. MVC activation was decreased (4.4-6.9%) throughout recovery, whereas submaximal contractions were minimally affected. Although overall, twitches were potentiated (15.5-19.8%) posttest, 3 MVCs had significantly greater twitch potentiation than 1 or 2 MVCs at 5 and 10 minutes. Results suggest that voluntary and evoked contractions respond differently to prior 10-second MVCs. In the present study, a warm-up routine of 1-3 MVCs of a 10-second duration did not enhance subsequent voluntary performance.
- Description: C1
- Description: 2003001186
- Authors: Behm, David , Button, Duane , Barbour, Glen , Butt, Jeremy , Young, Warren
- Date: 2004
- Type: Text , Journal article
- Relation: Journal of Strength and Conditioning Research Vol. 18, no. 2 (2004), p. 365-372
- Full Text:
- Reviewed:
- Description: The objective of this study was to investigate whether a warm-up consisting of a series of maximal contractions would augment the force and activation of subsequent leg extensor contractions. Both voluntary and evoked isometric contractions were tested to determine the mechanisms underlying the response. Nine subjects were tested for twitch, tetanic, submaximal (30%), and maximal voluntary contractile (MVC) properties before and after (1, 5, 10, and 15 minutes) one to three 10-second MVCs. MVC force either did not change following 1-2 MVCs or was depressed at 10 and 15 minutes after 3 MVCs. MVC activation was decreased (4.4-6.9%) throughout recovery, whereas submaximal contractions were minimally affected. Although overall, twitches were potentiated (15.5-19.8%) posttest, 3 MVCs had significantly greater twitch potentiation than 1 or 2 MVCs at 5 and 10 minutes. Results suggest that voluntary and evoked contractions respond differently to prior 10-second MVCs. In the present study, a warm-up routine of 1-3 MVCs of a 10-second duration did not enhance subsequent voluntary performance.
- Description: C1
- Description: 2003001186
- Joseph, Corey, Bradshaw, Elizabeth, Kemp, Justin, Clark, Ross
- Authors: Joseph, Corey , Bradshaw, Elizabeth , Kemp, Justin , Clark, Ross
- Date: 2014
- Type: Text , Journal article
- Relation: Sports Biomechanics Vol. 13, no. 3 (2014), p. 241-258
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- Description: Eccentric contractions that provide spring energy can also cause muscle damage. The aim of this study was to explore leg and vertical stiffness following muscle damage induced by an eccentric exercise protocol. Twenty active males completed 60 minutes of backward-walking on a treadmill at 0.67 m/s and a gradient of − 8.5° to induce muscle damage. Tests were performed immediately before; immediately post; and 24, 48, and 168 hours post eccentric exercise. Tests included running at 3.35 m/s and hopping at 2.2 Hz using single- and double-legged actions. Leg and vertical stiffness were measured from kinetic and kinematic data, and electromyography (EMG) of five muscles of the preferred limb were recorded during hopping. Increases in pain scores (over 37%) occurred post-exercise and 24 and 48 hours later (p < 0.001). A 7% decrease in maximal voluntary contraction occurred immediately post-exercise (p = 0.019). Changes in knee kinematics during single-legged hopping were observed 168 hours post (p < 0.05). No significant changes were observed in EMG, creatine kinase activity, leg, or vertical stiffness. Results indicate that knee mechanics may be altered to maintain consistent levels of leg and vertical stiffness when eccentric exercise-induced muscle damage is present in the lower legs. © 2014 Taylor & Francis.
The impact of strength level on adaptations to combined weightlifting, plyometric, and ballistic training
- James, Lachlan, Haff, Gregory, Vincent, Kelly, Connick, Mark, Hoffman, Ben, Beckman, Emma
- Authors: James, Lachlan , Haff, Gregory , Vincent, Kelly , Connick, Mark , Hoffman, Ben , Beckman, Emma
- Date: 2018
- Type: Text , Journal article
- Relation: Scandinavian Journal of Medicine & Science in Sports Vol. 28, no. 5 (2018), p. 1494-1505
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- Description: The purpose of this investigation was to determine whether the magnitude of adaptation to integrated ballistic training is influenced by initial strength level. Such information is needed to inform resistance training guidelines for both higher-and lower-level athlete populations. To this end, two groups of distinctly different strength levels (stronger: one-repetition-maximum (1RM) squat = 2.01 ± 0.15 kg·BM
- Authors: James, Lachlan , Haff, Gregory , Vincent, Kelly , Connick, Mark , Hoffman, Ben , Beckman, Emma
- Date: 2018
- Type: Text , Journal article
- Relation: Scandinavian Journal of Medicine & Science in Sports Vol. 28, no. 5 (2018), p. 1494-1505
- Full Text:
- Reviewed:
- Description: The purpose of this investigation was to determine whether the magnitude of adaptation to integrated ballistic training is influenced by initial strength level. Such information is needed to inform resistance training guidelines for both higher-and lower-level athlete populations. To this end, two groups of distinctly different strength levels (stronger: one-repetition-maximum (1RM) squat = 2.01 ± 0.15 kg·BM
Effectiveness of mouth rinsing versus ingesting pickle juice for alleviating electrically induced cramp in physically active adults
- Georgieva, Julia, Brade, Carly, Ducker, Kagan, Davey, Paul, Jacques, Angela, Ohno, Masato, Lavender, Andrew
- Authors: Georgieva, Julia , Brade, Carly , Ducker, Kagan , Davey, Paul , Jacques, Angela , Ohno, Masato , Lavender, Andrew
- Date: 2021
- Type: Text , Journal article
- Relation: Applied Sciences (Switzerland) Vol. 11, no. 24 (2021), p.
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- Description: (1) Background: Stimulating oropharyngeal transient receptor potential (TRP) channels in-hibits muscle cramping by triggering a supraspinal reflex to reduce α-motor neuron hyperexcitability. This study investigated whether the longer stimulation of the TRP channels via mouth rinsing with PJ is more effective than drinking PJ at inhibiting an electrically induced muscle cramp (EIMC). Both conditions were compared to the control (water). (2) Methods: The tibial nerves in 11 cramp-prone adults were percutaneously stimulated to elicit an EIMC of the flexor hallucis brevis in three trials that took place one week apart from each other. At cramp onset, the participants received mouth rinsing and expelling PJ (25 mL), ingesting PJ (1 mL·kg−1 body-mass (BM)), or ingesting water (1 mL·kg−1 BM). Cramp onset and offset were induced by electromyography, and the severity of discomfort was recorded using a visual analogue scale (VAS). (3) Results: The median time to cramp cessation as a percentage of water was 82.8 ± 14.63% and 68.6 ± 47.78% for PJ ingestion and PJ mouth rinsing, respectively. These results had large variability, and no statistically significant differences were observed. There were also no differences in perceived cramp discomfort between conditions, despite the hazard ratios for the time taken to reach VAS = 0, which was higher than water (control) for PJ ingestion (22%) and mouth rinsing (35%) (p = 0.66 and 0.51, respectively). (4) Conclusions: The data suggest no difference in cramp duration and perceived discomfort between PJ and water. © 2021 by the authors. Licensee MDPI, Basel, Switzerland. **Please note that there are multiple authors for this article therefore only the name of the first 5 including Federation University Australia affiliate “Andrew Lavender” is provided in this record**
- Authors: Georgieva, Julia , Brade, Carly , Ducker, Kagan , Davey, Paul , Jacques, Angela , Ohno, Masato , Lavender, Andrew
- Date: 2021
- Type: Text , Journal article
- Relation: Applied Sciences (Switzerland) Vol. 11, no. 24 (2021), p.
- Full Text:
- Reviewed:
- Description: (1) Background: Stimulating oropharyngeal transient receptor potential (TRP) channels in-hibits muscle cramping by triggering a supraspinal reflex to reduce α-motor neuron hyperexcitability. This study investigated whether the longer stimulation of the TRP channels via mouth rinsing with PJ is more effective than drinking PJ at inhibiting an electrically induced muscle cramp (EIMC). Both conditions were compared to the control (water). (2) Methods: The tibial nerves in 11 cramp-prone adults were percutaneously stimulated to elicit an EIMC of the flexor hallucis brevis in three trials that took place one week apart from each other. At cramp onset, the participants received mouth rinsing and expelling PJ (25 mL), ingesting PJ (1 mL·kg−1 body-mass (BM)), or ingesting water (1 mL·kg−1 BM). Cramp onset and offset were induced by electromyography, and the severity of discomfort was recorded using a visual analogue scale (VAS). (3) Results: The median time to cramp cessation as a percentage of water was 82.8 ± 14.63% and 68.6 ± 47.78% for PJ ingestion and PJ mouth rinsing, respectively. These results had large variability, and no statistically significant differences were observed. There were also no differences in perceived cramp discomfort between conditions, despite the hazard ratios for the time taken to reach VAS = 0, which was higher than water (control) for PJ ingestion (22%) and mouth rinsing (35%) (p = 0.66 and 0.51, respectively). (4) Conclusions: The data suggest no difference in cramp duration and perceived discomfort between PJ and water. © 2021 by the authors. Licensee MDPI, Basel, Switzerland. **Please note that there are multiple authors for this article therefore only the name of the first 5 including Federation University Australia affiliate “Andrew Lavender” is provided in this record**
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