Sex differences in skeletal muscle Flashcards
why would males have higher force production than females generally and what can this vary based on?
- males have a higher percentage of Type II fibres than females generally
- this is dependant on the muscle that is being observed and its function
why would females be more fatigue resistant in their muscles than males?
because females have a higher percentage of type 1 fibres in their muscles generally
in regard to firing rate and motor units, what is a difference between females and males and what is 1 similarity?
DIfference:
- females exhibit smaller motor units but the MUs discharge at higher firing rates
similarity:
- motor unit recruitment strategies between contraction levels are similar between the sexes
why do females tend to have higher firing rates than males
because they have smalller motor units, so they need a higher firing rate to produce the same force
when are differences between men and women in terms of firing rate eliminated between 10-25% MVC?
in dynamic (Isotonic) movement
what is testosterone significantly linked to?
Motor unit complexity
what is DHEA significantly linked to?
linked to Motor Unit Firing Rate
what 2 benefits can physical activity into older age facilitate in muscles, what can this prevent, and what is one potential drawback of the benefits involved
Benefits:
- more successful axonal sprouting
- reinnervation of denervated fibres
- these benefits prevent rapid loss of muscle strength
Potential drawback of benefits:
- benefits may be localised to muscles most invovled in the exercise, rather than peripheral muscles
when do majority of declines in muscles occur?
declines usually occur beginning at middle age
what differs in amount of decline between males and females in older age and what could influence this and outline how.
- firing rate differs between men and women in older age
- sex hormones, especially menopause for women, could influence neuromuscular adaptations to exercise across a life span
