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EMG and heart rate responses decline within 5 days of daily whole-body vibration training with squatting.

Rosenberger A, Liphardt AM, Bargmann A, Müller K, Beck L, Mester J, Zange J - PLoS ONE (2014)

Bottom Line: The heart rate (HR) response was significantly higher (P<0.05) during SE+V than during SE on all training days, but showed a constant decline throughout the training days.On training day 1, blood lactate increased significantly more after SE+V than after SE (P<0.05).On the following training days, this difference became much smaller but remained significantly different.

View Article: PubMed Central - PubMed

Affiliation: Institute of Aerospace Medicine, German Aerospace Center (DLR), Cologne, Germany; Institute of Training Science and Sport Informatics, German Sport University Cologne, Cologne, Germany.

ABSTRACT
In this study, we examined the acute effects of a 5-day daily whole-body vibration (WBV) training on electromyography (EMG) responses of the m. rectus femoris and m. gastrocnemius lateralis, heart rate (HR, continuously recorded), and blood lactate levels. The purpose of the study was to investigate the adaptation of muscle activity, heart rate and blood lactate levels during 5 days of daily training. Two groups of healthy male subjects performed either squat exercises with vibration at 20 Hz on a side alternating platform (SE+V, n = 20, age  = 31.9±7.5 yrs., height  = 178.8±6.2 cm, body mass  = 79.2±11.4 kg) or squat exercises alone (SE, n = 21, age  = 28.4±7.3 years, height  = 178.9±7.4 cm, body mass  = 77.2±9.7 kg). On training day 1, EMG amplitudes of the m. rectus femoris were significantly higher (P<0.05) during SE+V than during SE. However, this difference was no longer statistically significant on training days 3 and 5. The heart rate (HR) response was significantly higher (P<0.05) during SE+V than during SE on all training days, but showed a constant decline throughout the training days. On training day 1, blood lactate increased significantly more after SE+V than after SE (P<0.05). On the following training days, this difference became much smaller but remained significantly different. The specific physiological responses to WBV were largest on the initial training day and most of them declined during subsequent training days, showing a rapid neuromuscular and cardiovascular adaptation to the vibration stimulus.

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Excluded narrow frequency bands of the m. rectus femoris and m. gastrocnemius lateralis.The amplitudes of the EMG activity within the excluded narrow frequency bands at 20±2 Hz, 40.5±2.5 Hz, 61±2 Hz, and 82±2 Hz (means ±SD, µV) of all of the subjects for the m. rectus femoris (A) and m. gastrocnemius lateralis (B) of both legs during SE+V (○, n = 20) and SE (•, n = 21) on training days 1, 3, and 5. P-values were calculated for intervention group effects by repeated measures ANOVA.
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pone-0099060-g004: Excluded narrow frequency bands of the m. rectus femoris and m. gastrocnemius lateralis.The amplitudes of the EMG activity within the excluded narrow frequency bands at 20±2 Hz, 40.5±2.5 Hz, 61±2 Hz, and 82±2 Hz (means ±SD, µV) of all of the subjects for the m. rectus femoris (A) and m. gastrocnemius lateralis (B) of both legs during SE+V (○, n = 20) and SE (•, n = 21) on training days 1, 3, and 5. P-values were calculated for intervention group effects by repeated measures ANOVA.

Mentions: In the SE+V group, the EMG amplitude of the m. rectus femoris in the excluded narrow frequency bands (Figure 4A) was approximately 5% of the intensity of the EMG amplitude of the remaining natural EMG signal (Figure 2A). This EMG amplitude also increased linearly from series 1 to series 10, similar to the analyzed EMG amplitude around the excluded narrow frequency bands. In the SE group, the EMG amplitude of the m. rectus femoris in the excluded narrow frequency bands was approximately 2.5% of the intensity of the EMG amplitude of the remaining natural EMG signal, and it increased slightly from series 1 to series 10. The significantly higher EMG amplitude in the excluded narrow frequency bands of the SE+V group includes both, the non-synchronous natural EMG and the vibration-induced synchronous EMG.


EMG and heart rate responses decline within 5 days of daily whole-body vibration training with squatting.

Rosenberger A, Liphardt AM, Bargmann A, Müller K, Beck L, Mester J, Zange J - PLoS ONE (2014)

Excluded narrow frequency bands of the m. rectus femoris and m. gastrocnemius lateralis.The amplitudes of the EMG activity within the excluded narrow frequency bands at 20±2 Hz, 40.5±2.5 Hz, 61±2 Hz, and 82±2 Hz (means ±SD, µV) of all of the subjects for the m. rectus femoris (A) and m. gastrocnemius lateralis (B) of both legs during SE+V (○, n = 20) and SE (•, n = 21) on training days 1, 3, and 5. P-values were calculated for intervention group effects by repeated measures ANOVA.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4048290&req=5

pone-0099060-g004: Excluded narrow frequency bands of the m. rectus femoris and m. gastrocnemius lateralis.The amplitudes of the EMG activity within the excluded narrow frequency bands at 20±2 Hz, 40.5±2.5 Hz, 61±2 Hz, and 82±2 Hz (means ±SD, µV) of all of the subjects for the m. rectus femoris (A) and m. gastrocnemius lateralis (B) of both legs during SE+V (○, n = 20) and SE (•, n = 21) on training days 1, 3, and 5. P-values were calculated for intervention group effects by repeated measures ANOVA.
Mentions: In the SE+V group, the EMG amplitude of the m. rectus femoris in the excluded narrow frequency bands (Figure 4A) was approximately 5% of the intensity of the EMG amplitude of the remaining natural EMG signal (Figure 2A). This EMG amplitude also increased linearly from series 1 to series 10, similar to the analyzed EMG amplitude around the excluded narrow frequency bands. In the SE group, the EMG amplitude of the m. rectus femoris in the excluded narrow frequency bands was approximately 2.5% of the intensity of the EMG amplitude of the remaining natural EMG signal, and it increased slightly from series 1 to series 10. The significantly higher EMG amplitude in the excluded narrow frequency bands of the SE+V group includes both, the non-synchronous natural EMG and the vibration-induced synchronous EMG.

Bottom Line: The heart rate (HR) response was significantly higher (P<0.05) during SE+V than during SE on all training days, but showed a constant decline throughout the training days.On training day 1, blood lactate increased significantly more after SE+V than after SE (P<0.05).On the following training days, this difference became much smaller but remained significantly different.

View Article: PubMed Central - PubMed

Affiliation: Institute of Aerospace Medicine, German Aerospace Center (DLR), Cologne, Germany; Institute of Training Science and Sport Informatics, German Sport University Cologne, Cologne, Germany.

ABSTRACT
In this study, we examined the acute effects of a 5-day daily whole-body vibration (WBV) training on electromyography (EMG) responses of the m. rectus femoris and m. gastrocnemius lateralis, heart rate (HR, continuously recorded), and blood lactate levels. The purpose of the study was to investigate the adaptation of muscle activity, heart rate and blood lactate levels during 5 days of daily training. Two groups of healthy male subjects performed either squat exercises with vibration at 20 Hz on a side alternating platform (SE+V, n = 20, age  = 31.9±7.5 yrs., height  = 178.8±6.2 cm, body mass  = 79.2±11.4 kg) or squat exercises alone (SE, n = 21, age  = 28.4±7.3 years, height  = 178.9±7.4 cm, body mass  = 77.2±9.7 kg). On training day 1, EMG amplitudes of the m. rectus femoris were significantly higher (P<0.05) during SE+V than during SE. However, this difference was no longer statistically significant on training days 3 and 5. The heart rate (HR) response was significantly higher (P<0.05) during SE+V than during SE on all training days, but showed a constant decline throughout the training days. On training day 1, blood lactate increased significantly more after SE+V than after SE (P<0.05). On the following training days, this difference became much smaller but remained significantly different. The specific physiological responses to WBV were largest on the initial training day and most of them declined during subsequent training days, showing a rapid neuromuscular and cardiovascular adaptation to the vibration stimulus.

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