Bioenergetics Flashcards
Physical activity
any movement produced by muscle contractions, which result in an elevated energy expenditure above the basal metabolic rate ex: work, sports, leisure activities, daily activities
Exercise
Structured physical activity executed on a regular basis with the objective to improve fitness and/ or performance
Bioenergetics
the science that involves studies of energetic events in the biological world is called bioenergetics
Thermodynamics
The physical science dealing with energy exchange is called thermodynamics
Laws of thermodynamics
- Energy can neither be created nor destroyed 2. Whenever the energy is exchanged, the efficiency of the exchange will be imperfect and some energy will escape, usually in the form of heat
6 primary forms of energy
- thermal
- chemical
- mechanical
- electrical
- radiant
- atomic
3 ways energy is provided
Immediate (anaerobic galactic)
Non oxidative (anaerobic lactic)
Oxidative (aerobic)
General equation of bioenergetics
Echm (food)= Emch (work)+Ethrm (heat)
Metabolism oxidative equation
Food + O2–heat +co2+H2O
What is the upper limit of mechanical efficiency
25-30%
Mass
the amount of matter in a body measured in kg
Weight
is the force that results from the action of gravitation field on mass (N)
Unit for energy
Joule (J)
Unit for power
Watt (W)
What is 1 calorie in J
4.2 J
What is 1 kilocalorie in J
4.2 kJ
MET- metabolic equivalent
3.5 ml O2.kg-1.min-1
What is the energy equivalent of oxygen
the amount of energy needed to raise the temperature of one kilogram of water by one degree Celsius
Direct Calorimetry
Measurement of energy expenditure from body’s heat production
Indirect Calorimetry
Measurement of energy expenditure from the ratio between VO2 and VCO2
Numerical value of the energy equivalent of oxygen
1 litre of O2= 5kcal
What is a MET
the ratio of the rate of energy expended during an activity to the rate of energy expended at rest.
1 met is equal to 3.5ml.kg-1.min-1
ECR (energy cost of running)
1kcal.kg-1.km-1
Monosaccharides
one sugar