CARDIOVASCULAR & RESPIRATORY FITNESS ENERGY SYSTEMS CARDIOVASCULAR & RESPIRATORY FITNESS

Where does energy come from?

Where does energy come from?

Where does energy come from? The energy we derive from food is stored in the high-energy compound called Adenosine Triphosphate (ATP). It consists of 1 adenosine combined with 3 phosphate groups.

Where does energy come from? When acted on by the enzymes ATPase, the last phosphate group split away from the ATP molecule, rapidly releasing a large amount of energy.

Where does energy come from? At rest, the energy your body needs is derived almost equally from the breakdown of carbohydrates and fats. Proteins are your body’s building blocks, usually provide little energy for cellular production.

Where does energy come from? During mild to severe muscular effort (exercise), more carbohydrate is used, with less reliance on fats. In maximal, short duration exercise, ATP is generated almost exclusively from carbohydrates.

Where does energy come from? As the body breaks down these food components, energy is release in our body. However, about 60-70% of the energy expended by the human body is degraded to heat. The remainder is used to mechanical work and cellular activities such as growth and repair of muscles, active transport of substances across the cell membrane, muscle contraction and force production.

Where does energy come from? The process of storing energy by forming ATP from other chemical reactions is called phosphorylation. Through various chemical reactions, a phosphate group is added to a relatively low energy compound, ADP, converting it to ATP.

Where does energy come from? When these reactions occur without oxygen, the process is called anaerobic metabolism. When these reactions occur with oxygen, the overall process is called aerobic metabolism, and the aerobic conversion of ADP to ATP is called oxidative phosphorylation.

(1) Anaerobic Alactic Pathway aka. ATP-PC Take place in the cytoplasm Uses creatine phosphate Requires no oxygen Yields no by-product 100% intensity, good for 10-15 seconds

(2) Anaerobic Lactic Pathway aka. Glycolysis Takes place in the cytoplasm Requires the break down of glucose Requires no oxygen 80-95% intensity for 1-3 minutes Lactic acid is produced

(3) Aerobic Pathway aka. Cellular respiration Takes place in mitochondria Can use carbohydrate, fat, or protein for fuel Requires oxygen, produce lots of ATP 3 minute + until you run out of fuel No by-products

What’s the point? (1) Why is it important for us to learn the three energy systems? (2) How can you use this information in creating an exercise program for yourself or for someone else you are working with?

Cardiorespiratory Fitness refers to the ability of the circulatory and respiratory systems to supply oxygen to skeletal muscles during sustained physical activity.

Effects of regular cardio-respiratory exercise include: Increased size and mass of the heart Increased cardiac output (more blood is pumped with each heart beat) Increased number of arteries in trained skeletal muscle, which allow more blood to working muscles. Increased diameter of arteries in the heart Improve the strength and efficiency of respiratory muscles

Training Purpose? Athletic Performance Life-long Health

Assess cardiovascular fitness Harvard Step Test -step up and down on a platform at a rate of 30 steps per minute -for 5 minutes or till exhaustion -sit down and count the total heartbeat from 1-1.5 minutes, 2-2.5 minutes, then 3-3.5 minutes http://www.youtube.com/watch?v=mekPTS_LVv4&feature=related

Assessing cardiovascular fitness Harvard Step test Advantages: this test requires minimal equipment and costs, and can be self-administered. Disadvantages: Biomechanical characteristics vary between individuals. For example, considering that the step height is standard, taller people are at an advantage as it will take less energy to step up onto the step. Body weight has also been shown to be a factor. Testing large groups with this test will be time consuming.

Assessing cardiovascular fitness Beep Test -Continuous running between two lines 20m apart in time to recorded beep -The athlete's score is the level and number of shuttles (20m) reached before they were unable to keep up with the recording.

Assessing cardiovascular fitness Factors to consider: although the beep test is primarily a fitness test of the aerobic energy system, there are a range of other factors that can affect performance in the test and are are important to consider. These include: running efficiency and turning technique anaerobic capacity motivation and social dynamics motor skills and cognitive ability (especially in children) environmental differences clothing and running surfaces test familiarization and instructions

Assessing cardiovascular fitness Beep Test Advantages: Large groups can perform this test all at once for minimal costs. Also, the test continues to maximum effort unlike many other tests of endurance capacity. Disadvantages: Practice and motivation levels can influence the score attained, and the scoring can be subjective. This test is a maximal test, which requires a reasonable level of fitness. It is not recommended for recreational athletes or people with health problems, injuries or low fitness levels.

Assessing cardiovascular fitness Cooper 12 minute run -Participants run for 12 minutes and the total distance is covered is recorded. Walking is allowed, though the participant must be encouraged to push themselves as hard as they can.

Assessing cardiovascular fitness Results Table for Adult Males Rating Distance (meters) Excellent >2700m Good 2300-2700m Average 1900-2300m Below average 1500-1900m Poor <1500

Assessing cardiovascular fitness Cooper 12 minute run Advantages: large groups can be tested at once, and it is a very cheap and simple test to perform. Disadvantage: Practice and pacing is required, and performance on this test can be affected greatly by motivation.

Assessing cardiovascular fitness How do you know which is the most appropriate test to use? What would you do for a 65 year-old senior? What would you do for a 10 year-old boy? Why?

Monitor cardiorespiratory training Perceived Exertion (0-10 or 12-20 scale)

Monitor cardiorespiratory training Target Heart Rate Zone: The minimum heart rate level that is required in order for your body to receive cardiorespiratory fitness benefit. Calculate THR zone: Max HR = 220-age Lower limit 65% (220-age) Upper limit 85% (220-age)

Monitor cardiorespiratory fitness Recovery Heart Rate: Taken for 15 seconds after activity, then 1 to 3 minutes after the last aerobic activity.  The sooner the heart rate can return to ‘normal’ level the more efficient the cardiorespiratory system is working.

monitor cardiorespiratory fitness Talk test & breath sound check “climb no faster than you can talk”

Monitor cardiorespiratory fitness LEVEL Corresponding perceived exertion Corresponding HR If you can talk easily while working out Aerobic 2-4 100-110 bpm (50-60%) If you hear yourself breathing while working out Ventilatory Threshold 5-7 140-165 bpm (70-83%) If you can hear yourself breathing and can hardly talk Anaerobic threshold 8-10 Above 165 bpm 85% +

Monitor cardiorespiratory fitness (1) Which method of monitoring would you recommend for a 21 year-old track athlete? Why? (2) Which method of monitoring would you recommend for your 65 year-old grandma? Why?