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Article & Video Discussion / Re: jumpusa
« on: February 16, 2011, 02:16:28 pm »
Sorry for bumping an old topic, but i find this very interesting.
Some things i would like to share:
- All motor activities are started from the brain, namely the primary motor cortex (M1). Parts of the body have different motor areas in the M1. Signals are sent from the M1 to the muscles. Each neuron in the M1 sends signals to a number of different muscles. You cannot control which signals of the neuron are transmitted and which are not, so the other muscles get activated too (in a lesser degree). The neuron can only be switched on or off. The number of activated neurons can vary though.
Most of the time, the neuron's signal does not cross the midline (so the neurons on the left part of the M1 take care of activity on the left part of the body) (it does cross but it crosses back so general effect= homolateral)
However, a small part of the signals goes to the othe side. Meaning that activity in eg the left leg will cause activity in the right leg as well to a small degree.
- As for the bilateral deficit, our professor taught us that there is also something as a bilateral benefit. If you only train bilateral activities, it will apparently make you stronger in the bilateral activities, but when counting up the unilateral activities, there is a deficit in this sum. His example was for example professional rowers and ski jumpers.
Some things i would like to share:
- All motor activities are started from the brain, namely the primary motor cortex (M1). Parts of the body have different motor areas in the M1. Signals are sent from the M1 to the muscles. Each neuron in the M1 sends signals to a number of different muscles. You cannot control which signals of the neuron are transmitted and which are not, so the other muscles get activated too (in a lesser degree). The neuron can only be switched on or off. The number of activated neurons can vary though.
Most of the time, the neuron's signal does not cross the midline (so the neurons on the left part of the M1 take care of activity on the left part of the body) (it does cross but it crosses back so general effect= homolateral)
However, a small part of the signals goes to the othe side. Meaning that activity in eg the left leg will cause activity in the right leg as well to a small degree.
- As for the bilateral deficit, our professor taught us that there is also something as a bilateral benefit. If you only train bilateral activities, it will apparently make you stronger in the bilateral activities, but when counting up the unilateral activities, there is a deficit in this sum. His example was for example professional rowers and ski jumpers.