As said in the previous question, to replace all ATP it would take 3 – 5 minutes.
6. Explain why it is not possible to sprint at maximum pace for longer than approximately 10 seconds, but it is possible to sprint at maximum for 10 seconds, rest for 3 minutes and then sprint again for 10 seconds and repeat this cycle many times.
The creatine phosphate system is only the predominant energy source for up to 10 seconds in any exercise. It therefore is only used in fast, explosive movement such as a sprint. Because of its time restriction, it makes it not possible for an athlete to sprint any longer then 10 seconds. However, because ATP and phosphocreatine supples are restored between 3-5 minutes after the creatine phosphate system is used, it would make it possible to sprint again after rest. This can be done many times over, as the reproduction of these supplies never slows downs.
4. Sit-Ups
1. What fitness component is this laboratory testing?
This laboratory tests the fitness component of local muscular endurance.
2. What specific muscle group is it testing?
Sit-ups mostly test the abdominal area of the body. It can also apply contractions in the back.
3. What energy system is being used in this test?
The sit-ups test requires the use of both the Creatine Phosphate and Anaerobic Glycolysis systems. For the first 10 seconds where exercise first starts and the body reacts most explosively, the creatine phosphate system is predominant. For the majority of the minute of exercise, the anaerobic glycolysis system is at its peak. This energy system is used in activity with speed, muscular power and local muscular endurance that is relevant to the sit-ups test.
4. Explain why you cannot keep on doing sit-ups at your maximum rate.
The creatine phosphate system is the energy source used in maximal efforts but only lasts for 10 seconds. Because of this, you cannot keep on doing sit-ups at your maximum rate for longer then 10 seconds without a rest to build up more of this energy source.
5. Sit and Reach Test
1. What 2 areas of the body is this testing the flexibility of?
The sit and reach laboratory tests the flexibility of the lower back along with the hamstrings.
2. Compare the average score of boys and girls in this test. What physiological reason is there for these results?
The results of this test show that boys on average are less flexible then girls. This is due to hormonal differences that restrict a male’s ability to be flexible.
3. Give four examples of sporting skills which require a high level of flexibility and say what areas of the body are being flexed when performing each skill.
- Gymnastic events such as the Roman rings, uneven bars, parallel bars, floor routines and the beam. This needs flexibility in most areas of the body including the back, hip joints and shoulder joints.
- Goal keeping in hockey requires the flexion of the arms as the reach out to stop the hockey puck.
- Competitive aerobics also requires all round flexibility as it uses most body parts to produce spectacular movement.
- Defensive shuffle in netball and basketball requires more flexion in the hip and shoulder joints to produce a more extended block of the ball.
6. 400 Metre Sprint
1. What energy system is used predominately in this event
- during the first 10 seconds
- for the remainder of the run?
- During the first 10 seconds the creatine phosphate system is applied as the most predominant energy system
- For the rest of the run, the anaerobic glycolysis system will be most predominant. However, if the run outgoes 1 minute the aerobic system may take control.
2. Describe your feelings at the end of the run (muscles, breathing, etc) and explain in physiology terms why you felt this way. Use the terms O2 debt (alactacid and lactacid), stroke volume, heart rate etc.
I didn’t participate in this event, although I believe it would make the body feel tired and exhausted. Fatigue in muscles is due to a build up of lactic acid during anaerobic glycolysis. During the race tidal volume, heart rate, stroke volume and cardiac out put would have increased due to the extreme intensity and duration of the exercise. When finished, all four measures would slowly decrease to normal levels.
3.Why does light exercise (eg walking around or slow jogging) after this run, make u recover quicker?
After the run, you should walk or slow jog to help your body recover quicker to increase the levels of oxygen and blood circulation in your body. This helps get rid of lactic acid build up in the muscles.
7. Muscular Strength
1. What muscle group was tested?
This tested the strength of our handgrip. It therefore was using the flexors and extensors of the wrist and fingers.
2. Why are isometric strength machines able to produce greater gains in muscular strength?
The isometric strength machine is easy to perform and reliable in providing an index of muscular strength because it has a reasonably high correlation with total body strength.
3. “Males will always be superior in strength events to females” Discuss this statement.
Males generally do have a higher muscular strength than females. This is also because of hormonal differences. But, if a trained female, with a high muscular strength was to run against an average male of the same age, the female would have a chance of winning.
8. 20 Metre Shuttle Run Test
1. a) Calculate the VO2 maximum for all of the subjects and plot them on graph paper
b) What are the advantages and disadvantages of this test over other methods of assessing aerobic fitness?
a)
b) The advantages of this laboratory test is that it indicates a precise stage of the duration of your aerobic fitness. This helps to compare your aerobic fitness to other subjects. Disadvantages of this test, assessing your aerobic fitness, is that it is considered ideally suited to team games because it assesses aerobic capacity while also stimulating the stopping and starting nature of a team game. Stopping or starting may altar the results of your aerobic fitness.
2. What two other tests could be used to predict MVO2?
Two other tests that could be used to predict MVO2 are:
- A 12-minute swim test, to see how far the subject can swim in a 50m pool within the time limit.
- Or a 12-minute run test, to see how many metres can be run under the time limit.
Both of these tests reflect on whether or not the student has a well-developed aerobic capacity.
3. How do you rate your aerobic fitness? Explain why you performed as you did.
I rate my personal aerobic fitness as average. My shuttle run performance proves this, as I got a score that was fairly standard. A couple of factors may contribute to this. The most relevant is that I may contain more fast twitch (white) fibres then I do slow twitch (red) fibres which gives me more anaerobic skill then it does aerobic.
4. How is blood flow altered during exercise to the following?
a) brain
b) skeletal muscles
c) organs of the body
a) During exercise blood flow to the brain is decreased slightly.
b) Blood flow redistributes to the working muscles away from areas of the body that are less needed for the activity.
c) The organs of the body that aren’t needed in the activity whilst exercise also a restricted from blood flow, as the blood primarily moves to organs that are in more need. For example the digestive system would retrieve less blood flow then the lungs during exercise.
5. What factors contribute to increasing the oxygen supply to working muscles during exercise?
To increase the oxygen supply to working muscles during exercise a number of changes to various features of the respiratory system occurs:
- Breathing rate increases
- The amount of air inspired and expired with each breath exchange (Tidal Volume) increases.
- The amount of oxygen the body is able to uptake increases
- There are increased efforts from the ribcage muscles and diaphragm to enable increased expansion and contraction of the lungs.
6. Comment on the relative changes to
- heart rate
- stroke volume
- cardiac output
for a trained and untrained individual at rest and during exercise.
a) At rest, an individual with training would have a lower resting heart rate then an individual with no training. During exercise the effects are the same, with trained individuals having a lower heart rate then an untrained individual.
b) Stroke volume is greater at rest and during exercise for a trained athlete compared to an untrained person.
c) The amount of oxygen required by an individual while at rest basically does not alter as a result of their training status. However, during exercise trained athletes have a much more increased cardiac output then an untrained person.
7. Discuss the results of this lab. Do the MVO2’s for each subject compare favourably with those that you may have predicted prior to the lab?
For this lab, the male students proved to have a much higher MVO2 then the female students. I predicted this before the test was taken as most males seem to have a higher aerobic fitness state to females. For those in my class who are trained in a sport or activity also proved to have a higher MVO2 then those, like me, who are untrained in any event. An example of this is Daniel, who is a trained soccer player, scoring a MVO2 of 54.3 compared to myself, an untrained person, scoring 33.6.
Opposed to this it was evident that students with a lower MVO2 were those with a low fitness level, thus a low aerobic fitness.
9. a) Select two of the tests and describe training methods you could use to improve your performance in that test
1. Sit and Reach
Flexibility training is best done when the body is fully warmed up, this state is achieved generally after a training session or competition. Some methods to improve flexibility once warm are:
- To hold a stretch as far as comfortably possible for 20-30 seconds. This is known as static stretching.
- Once performing a static stretch you may contract the muscle for about 6-10 seconds against a resistance (a partner or a wall). This provides an increased stretched position.
Performing these methods over again, help to stretch the muscle, thus helping to improve flexibility.
2. 20 Metre Shuttle Run
To improve aerobic power needs continuos training. Most highly trained athletes of aerobic power have a minimum of three sessions per week. Training to improve aerobic power may include:
- Keeping the heart rate in the ‘training zone’ for at least 20 minutes for each session
- Participating in sports that offer the best aerobic activity, such as swimming, running and cycling
- Joining a local fitness centre that offers various forms of aerobic training such as aerobic classes, boxercise, spinning classes and pump circuits.
b) What would the effects of a long term cardiac vascular training program have on heart rate etc. (Chronic effects of training)
Sustained aerobic training results in the enlargement of the heart muscle itself. In endurance athletes, an increase in the size and volume of the ventricles of the heart occurs. This in turn significantly increases stroke volume. Long-term training also leads to an increase in the blood and oxygen supply of the heart muscle. This allows it to beat more strongly and efficiently during exercise and rest. Thus, giving the athlete a lower heart rate.
10. It is dangerous to make an assessment of a person’s ability in any test on the basis of one performance. Suggest 8 possible reasons why an individual might under-achieve in any of all of these tests on a particular day.
They might under achieve because of:
- Illness
- Injury
- Lack of motivation
- Lack of stretching which results in poor performance
- Low energy, from lack of food or sleep
- Lack of concentration
- Lack of arousal
- Lack of alertness
