ISEK 2024 - Day 3

Keynote speech: Sandra K Hunter

• Limit of motor perdoamce descline with age for both men and women. Physical activity can affect those limits.
• Even the most eliste athelete exhibit age-related decline. So what happens independednt of activity lebel.

age related loss of limb strngth & power

• Hunter 2000 Decline overall of strngth at 10% er decade of the knee extensor muscles of older women
• Afing of the nueromuscular syste:
  • limb power is more predictive of motor performance. It is about strngth of the msucle and speed of contraction?
  • With aging there is a slowing of the muscle
• There is an association between power olimb muscles and functionatil activity such as the ability to take the stairs or walk for 6 min
• A reduced power leads to fatigability

age-related changes within the neuromuscular system

- Brain atrophy with age is a given at 2% per decade
    - loss of grey matter, neurons and synapses with age but also loss of fibers as a result which leads to muscle atrophy
    - Fibers as well schrink with age. Type I fiber (slow fibers), type II (fast fiber) are even smaller (with age women losing more type II fibers.
- They looked at single muscle fiber to tell whether the loss of power is becayse of the overall less numerb fo fibers or that each individual fiber's power is less
    - the intrinsic stnegh of fiber is not impaired but its the size of the muscle masss

Dies neural drive to muscle change

- quantify the neural drive by stimulating during voluntary activation with transcranial stimulation?

fatigability

- For isometric tasks, the older adults (<75 years) ar not as fatigable as young adults
- For dynamic tasks, old adults are more fatigable during 

Session 1: PICs