King Grub
2013-09-18, 19:03
PURPOSE:
To examine the acute effects of dynamic stretching on leg extensor and flexor concentric peak torque, leg flexor eccentric peak torque, and the conventional and functional H:Q ratios.
METHODS:
Twenty-one women (mean ± SD age = 20.6 ± 2.0 yrs; body mass = 64.5 ± 9.3 kg; height = 164.7 ± 6.5 cm) performed maximal voluntary isokinetic leg extension, flexion, and eccentric hamstring muscle actions at the angular velocities of 60 and 180°·s before and after a bout of dynamic hamstrings and quadriceps stretching as well as a control condition.
RESULTS:
Leg flexion peak torque decreased under both control (mean ± SE for 60°·s= 75.8 ± 4.0 to 72.4 ± 3.7 Nm; 180°·s= 62.1 ± 3.2 to 59.1 ± 3.1 Nm) and stretching (60°·s= 73.1 ± 3.9 to 65.8 ± 3.3 Nm; 180°·s= 61.2 ± 3.3 to 54.7 ± 2.6 Nm) conditions while eccentric hamstrings peak torque decreased only following the stretching (60°·s= 87.3 ± 5.1 to 73.3 ± 3.6 Nm; 180°·s= 89.2 ± 4.4 to 77.0 ± 3.4 Nm) intervention (p ≤ 0.05). Stretching also caused a decrease in conventional H:Q (60°·s - 0.58 ± 0.02 to 0.54 ± 0.02; 180°·s - 0.67 ± 0.02 to 0.61 ± 0.03) and functional H:Q ratios (60°·s - 0.69 ± 0.03 to 0.60 ± 0.03; 180°·s - 1.00 ± 0.06 to 0.60 ± 0.03) (p ≤ 0.05).
CONCLUSIONS:
Since dynamic stretching reduced concentric and eccentric hamstrings strength as well as the conventional and functional H:Q ratios, fitness and allied-health professionals may need to be cautious when recommending dynamic, rather than static stretching to maintain muscle force.
Med Sci Sports Exerc. 2013 Sep 12. Effects of Dynamic Stretching on Strength, Muscle Imbalance, and Muscle Activation.
To examine the acute effects of dynamic stretching on leg extensor and flexor concentric peak torque, leg flexor eccentric peak torque, and the conventional and functional H:Q ratios.
METHODS:
Twenty-one women (mean ± SD age = 20.6 ± 2.0 yrs; body mass = 64.5 ± 9.3 kg; height = 164.7 ± 6.5 cm) performed maximal voluntary isokinetic leg extension, flexion, and eccentric hamstring muscle actions at the angular velocities of 60 and 180°·s before and after a bout of dynamic hamstrings and quadriceps stretching as well as a control condition.
RESULTS:
Leg flexion peak torque decreased under both control (mean ± SE for 60°·s= 75.8 ± 4.0 to 72.4 ± 3.7 Nm; 180°·s= 62.1 ± 3.2 to 59.1 ± 3.1 Nm) and stretching (60°·s= 73.1 ± 3.9 to 65.8 ± 3.3 Nm; 180°·s= 61.2 ± 3.3 to 54.7 ± 2.6 Nm) conditions while eccentric hamstrings peak torque decreased only following the stretching (60°·s= 87.3 ± 5.1 to 73.3 ± 3.6 Nm; 180°·s= 89.2 ± 4.4 to 77.0 ± 3.4 Nm) intervention (p ≤ 0.05). Stretching also caused a decrease in conventional H:Q (60°·s - 0.58 ± 0.02 to 0.54 ± 0.02; 180°·s - 0.67 ± 0.02 to 0.61 ± 0.03) and functional H:Q ratios (60°·s - 0.69 ± 0.03 to 0.60 ± 0.03; 180°·s - 1.00 ± 0.06 to 0.60 ± 0.03) (p ≤ 0.05).
CONCLUSIONS:
Since dynamic stretching reduced concentric and eccentric hamstrings strength as well as the conventional and functional H:Q ratios, fitness and allied-health professionals may need to be cautious when recommending dynamic, rather than static stretching to maintain muscle force.
Med Sci Sports Exerc. 2013 Sep 12. Effects of Dynamic Stretching on Strength, Muscle Imbalance, and Muscle Activation.