Adaptations to Resistance Training: Ex Phys

sex differences in distribution and use of muscle mass

• women have more of their muscle mass in lower body

• women tend to use upper body muscles less

• men typicall have more muscle mass

sex diiferences in percent muscle fiber type

• men have more muscle fibers, bigger muscle fibers, more type 2

• female skeletal muscl ecells are smaller

neural drive

males and female have simular and near maximal levels of drive

adipose

males ahve less relative body fat with sex differences in fat phenotypes

muscle fibers

males ahve greater proportional area of type 2 muscle fibers and smaller proportional area of type 1 fibers

skeletal muscle

males have larger muscle cross-sectional area, taken together with difference in muscle fibers, males have stronger, faster and more powerful muscles

heart

males have larger heart size, stoke volume, and cardiac output but simial maximal hear rate compared to females

lungs and airways

males have larger lung size and larger cross-sectional areas of conducting airways

red blood cells

males have higher hematocrit, hemoglobin, concentration, and hemoglobin mass

bones

males have longer, more dense, and stronger bones than females

important biological differences

• 99.98% of humans can be classified as male or female at birth based on their external genitals

• 0.018% are still male or female, just that their genitals are ambiguous

• there is no biological explanation for transgender

• no amount of training or nutrition can overcome the male athletic advantages

anabolic androgenic steroids

• class 3 controlled substance

• banned in most sports

• causes tissue growth (muscle)

testosterone

• primary androgenic hormone

• known has an anabolic agent

possible neural factors of strength gains

• resistance training benefits may carry over from one trained arm/leg to the other untrained arm/leg

• enhanced synchronizaion and recruitment of additional motor units for greater force production

• reduced coactivation of agonist and antagonist muscles

• changes in the neuromuscular junction

• increased rate coding or motor units

• increased neural drive