Static stretch
Explanation:
Static stretching exercises are done by elongating the target muscles as tolerated and then holding the stretch in that position for a stipulating length of time. This holding time period is usually determined by the individual’s age, activity level, any other previous illness or injuries etc.
The holding time usually is around 10-15 seconds is especially done to:
- Reduce risk of injury, muscle stiffness
- Increase mobility, flexibility, range of motion
- Relieve back or joint pains.
The main physiology in stretch reflex:
The stretch reflex is a myotatic reflex which is triggered by the action potentials of la afferent fibers. This causes the excited motor neurons to contract the stretched muscle which in turn reduces the potential.
The holding in static stretching is to make the elongation of the muscles a habitual length for the muscle spindle fibers and mark it is a new length.
The signals are reduced and the receptors are trained to allow more muscle fiber lengthening. The greatest increase in length or increase in range of motion occurs when the stretch is held for about 10-30 seconds with 2-4 repetitions.
The correct answer is C. The cousins are all within the normal range.
Chronic bronchitis and emphysema. :)
