Metabolism Overview

what does the first 30 seconds of exercise emphasize?

ATP-PC

what process provides most energy for first 2.5 minutes following ATP-PC?

glycolysis

During anaerobic exercise, pyruvate from glycolysis can be converted to_

lactate

when o2 is available, pyruvate

enters aerobic pathways instead

overview of aerobic pathways

substrates must go through various steps before entering aerobic pathways of mitochondria

-once in correct form, they enter krebs cycle and electron transport chain w/in mitochondria

Glycolysis occurs in

sarcoplasm of muscle cells

Glycolysis results in

ATP production from breakdown of glucose

glucose is supplied by

blood glucose or glycogen

glycolysis does not use ____ itself

oxygen

if pyruvate is converted to acetyl-CoA, acetyl-CoA can enter what type of pathway?

aerobic

If pyruvate is converted to lactate it is recycled through?

Cori cycle

Role of ATP in glycolysis

-atp required to begin glycolysis

-generates atp at the end

how much atp is produced if glycolysis starts with glucose?

2 ATP

how much atp is produced if glycolysis starts with glycogen

3 ATP

What happens to hydrogens during glycolysis

-they are produced and removed

-they are transferred to NAD to form NADH

Role of NADH

transports hydrogens to mitochondria for use in aerobic metabolism for use in aerobic metabolism

lactate energy system

if aerobic metabolism does not accept hydrogens, pyruvate
(from the last reaction of glycolysis) can accept the
hydrogens to become lactate

glycolytic enzymes

improve performance by increasing atp availability from glycolysis

Glycogen phosphorylase

breaks down intramuscular glycogen to glucose

Phosphofructokinase (PFK)

rate limiting step of glycolysis

-has most impact of the enzymes

Lactate dehydrogenase (LDH

pyruvate to lactate

factors that increase enzymes

weight, sprint, endurance training, temp, pH

a(n) _______ in IM glycogen affect glycolytic and aerobic production of atp

increase

what kind of training increases IM glycogen?

endurance training

factors impacting im glycogen in weight and activities

-length of training program

-type of training

Buffering Capacity Adaptation

improve ability to buffer acidity of hydrogen ions produced in glycolysis

-increases performance and recovery in activities that increase IM acidity

Intracellular buffers are located in

skeletal muscle

examples of intracellular buffers

proteins, phosphate groups, bicarbonate

bicarbonate + H+ =

sodium bicarbonate (converts strong acid to carbonic/weak acid)

phosphate + H+=

sodium phosphate (converts strong to weak acid)

Protein + H+=

COO- group of protein

Ammonia group of protein

combines w H+ in presence of excess acid

when does anaerobic metabolism provide majority of energy?

during high intensity, short duration maximal physical activity (ex sprints)

when does aerobic metabolism provide majority of energy?

long duration, low intensity physical activity (ex.marathon)

anaerobic activity relies on ____ and _____ for energy

IM ATP and PC