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Effects of Cooling on Ankle Muscle Strength, Electromyography, and Gait Ground Reaction Forces.

Halder A, Gao C, Miller M - J Sports Med (Hindawi Publ Corp) (2014)

Bottom Line: The effects of cooling on neuromuscular function and performance during gait are not fully examined.There was a significantly reduced isometric maximum force in the TA muscle (P < 0.001) after cooling.We found no significant changes in the gait GRFs and RCOF on dry and level surface.

View Article: PubMed Central - PubMed

Affiliation: Division of Ergonomics and Aerosol Technology, Department of Design Sciences, Faculty of Engineering, Lund University, P.O. Box 118, 221 00 Lund, Sweden.

ABSTRACT
The effects of cooling on neuromuscular function and performance during gait are not fully examined. The purpose of this study was to investigate the effects of local cooling for 20 min in cold water at 10°C in a climate chamber also at 10°C on maximal isometric force and electromyographic (EMG) activity of the lower leg muscles. Gait ground reaction forces (GRFs) were also assessed. Sixteen healthy university students participated in the within subject design experimental study. Isometric forces of the tibialis anterior (TA) and the gastrocnemius medialis (GM) were measured using a handheld dynamometer and the EMG was recorded using surface electrodes. Ground reaction forces during gait and the required coefficient of friction (RCOF) were recorded using a force plate. There was a significantly reduced isometric maximum force in the TA muscle (P < 0.001) after cooling. The mean EMG amplitude of GM muscle was increased after cooling (P < 0.003), indicating that fatigue was induced. We found no significant changes in the gait GRFs and RCOF on dry and level surface. These findings may indicate that local moderate cooling 20 min of 10°C cold water, may influence maximal muscle performance without affecting activities at sub-maximal effort.

No MeSH data available.


Related in: MedlinePlus

Example of GRFs and RCOF used for analysis, the vertical force (Fz), longitudinal shear force (Fy), and transverse force (Fx) during the HS and TO phases. The second peak of Cofy indicated by an arrow at the bottom represents the RCOF during heel strike.
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fig5: Example of GRFs and RCOF used for analysis, the vertical force (Fz), longitudinal shear force (Fy), and transverse force (Fx) during the HS and TO phases. The second peak of Cofy indicated by an arrow at the bottom represents the RCOF during heel strike.

Mentions: The ratio of shear to normal ground reaction force, termed the required coefficient of friction (RCOF) [29], was calculated for each trial by dividing longitudinal anterior-posterior force by vertical force (Fy/Fz). According to Chang et al. [25] RCOF was generally accepted to be the value of the third peak of the RCOF versus time curve, as shown in (Figure 5) below. The third peak was scrutinized from GRF curve by selecting the time period from 20 milliseconds to 200 milliseconds after heel contact (when Fz reached 10 N); however, on a few occasions the third peak was unclear so the second peak was used instead.


Effects of Cooling on Ankle Muscle Strength, Electromyography, and Gait Ground Reaction Forces.

Halder A, Gao C, Miller M - J Sports Med (Hindawi Publ Corp) (2014)

Example of GRFs and RCOF used for analysis, the vertical force (Fz), longitudinal shear force (Fy), and transverse force (Fx) during the HS and TO phases. The second peak of Cofy indicated by an arrow at the bottom represents the RCOF during heel strike.
© Copyright Policy - open-access
Related In: Results  -  Collection

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getmorefigures.php?uid=PMC4590893&req=5

fig5: Example of GRFs and RCOF used for analysis, the vertical force (Fz), longitudinal shear force (Fy), and transverse force (Fx) during the HS and TO phases. The second peak of Cofy indicated by an arrow at the bottom represents the RCOF during heel strike.
Mentions: The ratio of shear to normal ground reaction force, termed the required coefficient of friction (RCOF) [29], was calculated for each trial by dividing longitudinal anterior-posterior force by vertical force (Fy/Fz). According to Chang et al. [25] RCOF was generally accepted to be the value of the third peak of the RCOF versus time curve, as shown in (Figure 5) below. The third peak was scrutinized from GRF curve by selecting the time period from 20 milliseconds to 200 milliseconds after heel contact (when Fz reached 10 N); however, on a few occasions the third peak was unclear so the second peak was used instead.

Bottom Line: The effects of cooling on neuromuscular function and performance during gait are not fully examined.There was a significantly reduced isometric maximum force in the TA muscle (P < 0.001) after cooling.We found no significant changes in the gait GRFs and RCOF on dry and level surface.

View Article: PubMed Central - PubMed

Affiliation: Division of Ergonomics and Aerosol Technology, Department of Design Sciences, Faculty of Engineering, Lund University, P.O. Box 118, 221 00 Lund, Sweden.

ABSTRACT
The effects of cooling on neuromuscular function and performance during gait are not fully examined. The purpose of this study was to investigate the effects of local cooling for 20 min in cold water at 10°C in a climate chamber also at 10°C on maximal isometric force and electromyographic (EMG) activity of the lower leg muscles. Gait ground reaction forces (GRFs) were also assessed. Sixteen healthy university students participated in the within subject design experimental study. Isometric forces of the tibialis anterior (TA) and the gastrocnemius medialis (GM) were measured using a handheld dynamometer and the EMG was recorded using surface electrodes. Ground reaction forces during gait and the required coefficient of friction (RCOF) were recorded using a force plate. There was a significantly reduced isometric maximum force in the TA muscle (P < 0.001) after cooling. The mean EMG amplitude of GM muscle was increased after cooling (P < 0.003), indicating that fatigue was induced. We found no significant changes in the gait GRFs and RCOF on dry and level surface. These findings may indicate that local moderate cooling 20 min of 10°C cold water, may influence maximal muscle performance without affecting activities at sub-maximal effort.

No MeSH data available.


Related in: MedlinePlus