Training Adaptations
Jan 13, 2016
Training Adaptations
LIVER
SKELETAL MUSCLE TISSUE
Adrenal Gland
Adipocytes
Mitochondria
TRAINING WILL:
Decrease RER
Does not effect sub-max oxygen uptake
Increases LT and lowers muscle and blood lactate at any sub-max workload
Aerobic training can cause 50-100% increases in mitochondrial mass per gram of skeletal muscle.
However, when express per gram of mitochondrial protein training does not alter specific activity.
Total CHO:
Pre = 145 umol/min
Post = 100 umol/min
or a 50% decrease
This is due to decrease reliance on blood glucose and muscle glycogen
Training decreases Ra(rate of appearance) of glucose from the liver. This means less glycogen depletion in liver.
Muscle Glycogen Depletion
With training you can double your mitochondrial mass, thus at any giving work load each mitochondrion will only be working (ie producing ATP) at half the rate it was before training. The main stimulus for increases in oxidative phosphorylation is ADP. Therefore the increase in intracellular ADP must be less in trained individuals.
blood lactic acid
Training Adaptations
# mitochondria
epi/norepi release during exercise
muscle & liver glycogen use
intramuscular fat use
# MCT’s (via mitochondria)
CAT I (ß-oxidation)
cAMP
Training Adaptations (cont.)• Two major changes that occur with training
1.) # mitochondria in muscle cellscan be doubled at most
2.) epi/norepi release during exercisetraining sympathetic activity at any given work load
Benefits of adaptations to training• 1.) Glycolysis
– Spares CHO, liver glycogen– maintains blood glucose (CNS)– mechanisms:
catecholamines PFK activity mitochondria faster ATP generation,
[AMP&ADP] PFK activity2.) Blood Lactic Acid
keeps blood pH normalmechanisms:
glycolysis mitochondria (more MCTs)
Benefits of adaptations to training (cont.)
• 3.) Fat use fat use from adipocytes via epi/norepi fat use from intramuscular TGs– mechanisms:
mitochondria (via in CAT I activity)
• acetyl CoA production PFK glycolysis
Take home point:*Training glycolysis & Fat use via mitochondria & catecholamines*
Muscle Glycogen vs. FFA Expenditure