Kinesiology 2230A/B Study Guide - Winter 2018, Comprehensive Midterm Notes - Raquel Turner, Oxygen, Muscle Contraction
11 Oct 2018
School
Department
Course
Professor
Kinesiology 2230A/B
MIDTERM EXAM
STUDY GUIDE
Fall 2018
Energy 2230 Raquel Moses
Lecture 1:
Metabolism During Exercise:
- Energy is never created nor destroyed; it’s transformed from one form to another
o Source: from the sun which generates its energy through gravitational sources by fusing
hydrogen atoms and forming helium
- Solar Energy: we’re catching waves from the sun into electrical energy and same with wind
energy
o Nuclear energy is done by nuclear fission
- Aurora Borealis: collisions between gaseous particles in Earth’s atmosphere interact with charged
particles released from sun’s atmosphere (Creates the northern lights)
Race Length and Energy Systems
- Difference in contractile units within the muscle
o The shorter the race, the faster you can run, the more power the muscle must generate
- During the first few seconds you can generate and use lots of energy and run really fast (ATP-
PCr), after that you rely on anaerobic glycolysis to give you energy and slow down until you
steady out aerobically)
o The longer you run, slower you’re going to move; as duration continues you run slower
o Looking at aerobic system when you run a long time
What is Energy?
- Potential to do work (exercise)
- Quantifying Energy:
o Energy in biological reactions produces heat
▪ Energy intake and output are measured either in kilocalories (kcals) or joules
(1kcal = 4.184kjoules)
▪ 1kcal (or 4.2kjoules) represents the amount of energy necessary to raise the
temperature of 1kg of water by 1 degree Celsius at 15 degrees Celsius
Efficiency During Exercise:
Efficiency = Work Produced/Free energy of ATP = Output/Input = Watts/VO2 = kcals/kcals
- Efficiency: amount of energy released at a given point of time and how much work can be done
with that energy
- 70-80% of energy used in our bodies is released as heat; inefficient
o Chemical reactions occurring in muscle generate heat for maintaining body temperature
(we’re homeotherms)
o Inefficient because at rest, all metabolic processes result in heat production (37°C) –body
tries to produce this temp for homeostasis
▪ At rest, all metabolic processes result in heat production (37 degrees Celsius)
- Muscle contraction indicate the existence of exothermic chemical reactions (release heat)
o Exothermic reactions: reactions that release energy/heat
- Oxygen consumption is a reflection of how much energy we’re producing
o Using oxygen because we need it to complete the aerobic pathway so we can form ATP
to do work
o We can convert VO2 into kcals and Watts into kcals
▪ When we do that we can determine efficiency
find more resources at oneclass.com
find more resources at oneclass.com
Energy 2230 Raquel Moses
Nutritional Sources of Energy:
- Carbohydrates, Fats, and Proteins
o All made of carbon, hydrogen, and oxygen - addition of nitrogen in the case of protein
o Carbohydrate (CHO) stored in muscle and most readily available
o Hydrogens indicate how much energy is in the compound
- When talk about metabolism, the series of reactions are initially working with substrate that have
relatively similar molecular structures
- Makes more sense to store things as fat as a volume perspective –need more carbs to match the
volume of fats
Body Stores of Fuels and Energy:
- Carbohydrates:
o Very little glucose in the bloodstream
o Brain runs on glucose
o Very little CHO available in blood
o Lots of CHO in muscle (500g, 2050kcal) and significant amount in liver (110g, 451kcal)
▪ Found in very low quantities in blood fluids
▪ Total: 625g, 2563kcal of CHO in body
o Need to break down glycogen in liver and transport it to working muscle, takes time
o Enough cards for ~4hours of light exercise
- Fat:
o Looking at subcutaneous fat (7718g, 72549kcal)
▪ Fat is stored in muscle too (161g, 1513kcal)
*Estimates based on body weight of 65kg male with 12% body fat*
Why don’t we want to store more carbs if they’re easier to get at than fats?
- The energy yield from 1g of CHO is 4kcal and 1g of fat is 9kcal
o 2x the energy from 1g of fat than 1g of carbs if using fats as substrate for metabolism
- As we break down the compounds we release energy
o Different amounts of energy released from break down of CHO than fats
- Hydrogens are important because when they’re removed from CHO and fats they move through
the ETC and combine with O2 at the end
o This yields ATP
CHO-Glycogen (Storage):
- Glycogen: how glucose is stored in liver and muscle
o Series of glucose molecules bound with water→When we store glycogen, we store water
o Water + glucose binds together; the weight per gram of glycogen is part water, but we
cannot get energy from water so some weight is not used for energy
▪ When add water, we’re increasing the weight but not increasing the energy,
so per gram of glycogen (compared to glucose) we’re getting less energy
Fats-Triglycerides:
- Glycerol backbone with 3 fatty acids bound to it
- Holds a tremendous amount of energy
- Store energy as fat even though glycogen is easier to process because triglycerides (fats) have lots
of hydrogens, therefore, very energy efficient
find more resources at oneclass.com
find more resources at oneclass.com
Document Summary
Energy is never created nor destroyed; it"s transformed from one form to another: source: from the sun which generates its energy through gravitational sources by fusing hydrogen atoms and forming helium. Solar energy: we"re catching waves from the sun into electrical energy and same with wind energy: nuclear energy is done by nuclear fission. Aurora borealis: collisions between gaseous particles in earth"s atmosphere interact with charged particles released from sun"s atmosphere (creates the northern lights) Difference in contractile units within the muscle: the shorter the race, the faster you can run, the more power the muscle must generate. During the first few seconds you can generate and use lots of energy and run really fast (atp- Efficiency = work produced/free energy of atp = output/input = watts/vo2 = kcals/kcals. Efficiency: amount of energy released at a given point of time and how much work can be done with that energy.
