Stats and tests Flashcards
Error bars are a graphical representation of the variability of data
ERROR BARS: Bars on the graph showing error.
STANDARD ERROR BARS: Very small percentage. No matter what, it does not really change.
STANDARD DEVIATION ERROR BARS: Always changing. Dependent on the number that you have so far.
For example, two golf putts. Two players. 10 balls each and they are putting from 10 yards. 10 shots. We can give them a MEAN, an average number out of their 10 shots, on how close they are. Player one has a smaller mean than player 2. You could argue that player one is more consistent because more of them have ended up closer to the pin. This is when the standard deviation bar enters. Although player 2 has a higher mean, it has a smaller standard deviation. The spread around the mean is smaller. This would infer that player 2 is actually more consistent. However, it could also be that player 1 put one in the hole and maybe two in the hall out of 10 and the others quite far away. If these two players were to do it again, one would expect player 2 to have similar results, player one doesn’t know. Big standard deviation = No guarantee in the reliability. No guarantee it can be repeated.
The mean and standard deviation of a set of values
Mean: Add all of the values and divide by the number of values.
Standard deviation can also be about reliability in a data set.
Statistical standard deviation is used to summarize the spread of values around the mean, and that within a normal distribution approximately 68 % and 95 % of the values fall within plus or minus one or two standard deviations respectively.
Player 2 has a better mean and standard deviation now. Player 2 would more than likely reproduce this outcome more consistently.
BELL CURVE: The amount of standard deviation when you calculate it. Once you have that number, one standard deviation is to take away that number from the mean, from both sides. Add it and subtract it and within that range is one standard deviation. This can be done with two standard deviations. Get the standard deviation, time it by two, add it to the mean, take it away from the mean and that range is two standard deviations.
To produce normally distributed data, you need 68 % of the data to fit within the bracket. Within 2 standard deviations, 95 %. Within 3 standard deviations, 100 %.
If the mean is 5 and 1 standard deviation is 3: We add three and we take away three from the mean. So, 2 and 8. So, every shot that is between 2 and 8 yards, gets ticked. Add the ticks up and this 70 % is within one standard deviation. Two standard deviations are 6. So, 0 to 11, by adding and taking away the 6. Hence, every value gets ticked. Add them up: 100 %.
Normal distribution: One standard deviation 68 % or more.
Standard deviation measures how much a set of data varies from the mean. It informs about the spread of data, and is an estimate of the average variability. How much it varies around that mean. This spread of data is measured in the same units of measurement as the original data. It can also be calculated by figuring out the square root of variance.
A small standard deviation means that the data is cluttered close to the mean and is reliable. Large standard deviation means there is a wide spread around the mean.
Even if data sets have the same mean, that does not infer that they have a similar standard deviation.
Coefficient of variation
Standard deviation expressed as a percentage. It puts it in relative terms when comparing data sets with different means.
Practicing over 20 yards and at 10 yards, by putting them in percentage you can compare.
Athletics example. Sprint or distance. This would allow a coach to compare vast differences in times, simply by comparing them into a percentage to assess performance.
Standard deviation / Mean x 100.
Significance of the difference between two sets of data using calculated values for t and the appropriate tables.
T-TEST: Statistical significance.
When you want to look at statistical differences between two data sets.
You’re not looking at how many ice creams a nice green man sells on a hot day. Could be a relationship on two axis, x and y, you would look for a correlation between the two, not the reliability and repeatability of the data. That is the standard deviation.
Here, you are comparing. What we are looking for in a T-test is error and the significance of that error. So that is in the form of a value, a P-VALUE.
P-VALUE. What you want to prove with your T-test is that the statistics are 0.05 or lower. Putting it into a percentage, 0.05 is 5 %. What you are stating is that your data is 95 % without error. Then, the statistics and results are significant. If it is higher than 0.05, then it is insignificant.
UNPAIRED T-TEST: Different groups, tested once. Independent of the variable. For instance, male vs females to see cardiovascular, muscular, respiratory, speed response. The variable stays the same but you are applying two different groups to that variable.
PAIRED T-TEST: The same group tested twice, depending on the changing variable. For instance, change in temperature or mode of exercise. Play basketball in a room with AC and then outside in hot weather. It might be blood pressure changes being evaluated, for instance, or core temperature, or the bleep test or Vo2 max, 12 minute cooper’s run. Same variable but changing the environment. Response changes.
Existence of a correlation does not establish that there is a causal relationship between two variables
CORRELATION: Used to describe a relationship between variables. Even though it appears so, correlation does not imply a causal relationship. Correlation indicates the magnitude of a relationship.
Correlation coefficient is a positive or a negative value expressed in between -1 and 1.
0 - no relationship.
- negative relationship.
+ positive relationship.
The taller the basketball player, the more rebounds they will collect. If you’re taller, you’re more likely to take more rebounds than someone who is shorter. But just because you’re taller does not mean you are going to take more rebounds than someone who is shorter.
Importance of specificity, accuracy, reliability and validity with regard to fitness testing
SPECIFICITY: Ensuring the test is specific to the performer.
If you are testing a swimmer, they have to be in the pool. If you are testing a football player, it makes sense to do the test at a football pitch. If the test is for power, you wouldn’t do a 30 meter sprint test. You would do broad jumps to test the power of the legs of the athlete.
ACCURACY: Ensuring that the equipment used can be precise in recording data. For instance, if to record times one gives a stopwatch to each sprinter, there is no way to guarantee that they started them at the same time.
RELIABILITY: Ensuring the protocol is adhered to each and every time the test is administered. Setting up the test well, etc.
VALIDITY: Ensuring that the test is suitable for the desired fitness outcome. To measure power, there is no point in doing the sit and reach test. The test has to be suitable.
Importance of study design in the context of the sports, exercise and health sciences
RESEARCH QUESTION: Identification of the research question. Is there a specific problem identified?
VARIABLES
INDEPENDENT: Independent to the study, changing variables.
DEPENDENT: The study is dependent on this variable. This is what one is measuring.
HYPOTHESIS: A prediction as to what is going to happen within the study, based upon limited information.
NULL HYPOTHESIS: Opposite of the hypothesis.
LITERATURE: Review relevant literature related to the study. Regarding variables, methods of data collection, types of statistical tests. Other studies, journals, official scientific documentation.
TESTING: Testing needs to be specific, accurate, reliable and valid. Is retesting applicable, if so, what is the timeframe?
DATA COLLECTION: What data collection method will work best for the tudu. Are you trying to prove significant difference, a relationship or reliability? Ensure that enough data is recorded.
CONTROLS: How is the data method constructed?
PLACEBO: one sample giving a placebo.
BLIND: subjects are not aware of what they are being tested for.
DOUBLE BLIND: subjects and researchers are unaware of who is being for what.
RANDOMISATION: Randomly assigned sample group.
LIMITATIONS: It is important to know, and recognise, the limitations of the study.
CONCLUSION: Draws a close to the study by summarising the relevant literature, with your outcome from the study, whilst justifying your hypothesis.
ETHICS: What ethical considerations are relevant to the study.
ADHERENCE TO HEALTH AND SAFETY: Taking a PAR-Q, shortly appropriate warm-ups, assistance with machinery, ensure subjects are aware they can stop if needed.
INFORMED CONSENT: Subjects are performing at their own will, and have provided written consent to prove this.
Importance of the Physical Activity Readiness
Pre-exercise screening is a key principle before sedentary individuals start becoming more physically active. Determining one’s readiness for physical activity involvement is a prudent and important first step in the fitness assessment and exercise prescription process.
PAR-Q has been recommended prior to how to moderate exercise involvement.
It can be self-administered at one’s own convenience.
PAR-Q is composed of seven questions that have been shown to be sensitive for detection of pre existing medical conditions / injuries.
If an answer is yes to one or more of the PAR-Q questions it is essential to consult with your doctor before commencing an exercise programme.
If the answer is no to all PAR-Q questions, it can be reasonably assumed that it is safe to become physically active.
The possibility of undetected serious disease is diminished by administering the test.
The test not only helps you determine the readiness to begin exercise, it also determines the readiness to intensify a physical activity/exercise programme.
PAR-Q is designed to prevent sudden death syndrome, however, more commonly designated to prevent muscle/joint/bone injuries.
Information then can be disclosed to the gym and talked about with the doctor.
Medical, injury history are important. Also as exercise trends, lifestyle and fitness goals.
Field, laboratory, sub-maximal and maximal tests of human performance
FIELD TESTING: A test that is conducted in the natural habitat of the sport, not requiring specific equipment to conduct the test. To test a tennis player’s power when doing shots, the test will be conducted at a tennis court.
Illinois agility test, swimming bleep test, running bleep test.
Easy to set up. Usually cheap and effective. Specific to the sport.
Can lack accuracy. Require level of motivation. Usually completed in groups, so other factors may disrupt accuracy of results (peer pressure, anxiety, self esteem).
LAB TESTING: Usually conducted in a controlled environment, using specialist equipment. Great to evaluate Vo2 Max. Easier access to it if you are an elite player.
VO2 MAX test, Wingate test, force plate test.
Accurate component of fitness. Results can precisely inform training design. Individually completed, eliminated external factors.
Usually expensive equipment required, chance of injury, not sport specific.
SUB MAXIMAL TESTING: A test that does not require a performer to reach the maximal effort levels. Instead, it predicts maximal effort levels based upon sub maximal efforts. Big problem is that it depends how hard you work, how much effort you put in. Bleep test, 12 minute cooper test, it depends on the effort you put in. It is not as accurate as doing a VO2 max test, but much more accessible.
Harvard step test, Astrand test, The Bruce Treadmill test.
Less stressful / less chance of injury. Can repeat in a short time frame. Good correlation with maximal tests.
Estimation of maximum fitness. Hard to set intensity accurately. Level of motivation required.
MAXIMAL TESTING: A test where the performer releases short term exhaustion, whilst attempting to reach maximal effort levels.
One rep max, Wingate test, Vo2 max test, 30m sprint test.
Accurate measure of fitness. Accurate results, allows specific training targets to be set, strict protocol and administration making retest comparisons reliable.
Chance of injury. Cannot repeat within a short time frame. Might not complete the test, yielding no result for the performer.
Essential elements of a general training programme
WARM UP / STRETCHES: Pulse raiser (get heart rate up, warm muscles) / Dynamic Stretches (held for 10 seconds each, to increase range of movement on a short-term basis, prevent injury during exercise. After the pulse razor because the muscles need to be warmed before stretching. Like gum) / Related activity (to the sport you are about to play. Before playing basketball, it makes sense to do some dribbling and handling and shooting with the ball. Maybe some 1v1).
ENDURANCE TRAINING: 60-80 % HR MAX (the fitter you are, the closer you are to 80 %) of your maximum. The more fitness gains will take place) / Specific (if you are a swimmer, train in the pool) / Targeted muscle groups (that are needed for the performance).
COOL DOWN / STRETCHES: To get the heart rate down gradually to a resting state (important to prevent blood pooling. Slow walk, hands on head to encourage deep breathing) / Static stretches (held for 30 seconds. No movement. Improves flexibility and prevent injury) / Prevention.
FLEXIBILITY TRAINING: PNF / Stretches / Yoga/Pilates.
RESISTANCE TRAINING: Body weight / Weights / Power, strength or endurance (to prepare for performance and prevent injury).
More weight with less reps: Power.
8-12 reps of a heavy weight: Strength.
Lighter weight, many reps, 15+: Endurance.
A Basketball player might work on tricep shoulder movement, a golfer on the torso.
RECREATIONAL ACTIVITIES: Additional components of fitness that would benefit the performance. Enhance motivation and team building. For instance, football players doing cricket.
Key principles of training programme design
PROGRESSION: A gradual increase in the workload of exercise. This is to avoid a plateau in the level of fitness.
OVERLOAD: An athlete must overload the system they are working. This is how progression takes place. An increase in frequency per week, intensity and / or duration (time) of training will apply to a performer’s programme.
SPECIFICITY: The training must match the needs of the specific sport / activity. For example, a swimmer would do most of their training in the pool, a footballer winger would work on agility (turns, jumps and dummies), and a sprinter would focus on straight line power, strength and speed work. Specific to sport and the position.
REVERSIBILITY: To be avoided. Can be brought about by injury, demotivation or a lack of progressive overload. It could happen if an athlete does not get out of a plateau too. An athlete will experience reverse fitness effects as a result of training less frequently. General rule of thumb: You lose fitness twice as fast as you gain it. So, gains from a 4 week programme will be lost within 2 weeks of non training.
VARIETY: Prevents boredom. Vital for motivation and desire to progress and maintain required intensity levels.
PERIODISATION: Training is performed in cycles. Each cycle differs in intensity, specificity and volume of work. By cycling, the body adapts to its ever changing environment and can allow performers to reach peak performance at the right time. For example, boxers and athletes preparing for an event.
Ways in which exercise intensity can be monitored
Heart rate predicts exercise intensity. Increases inline with exercise intensity. Indicates maximum volume of oxygen that can be consumed (VO2 MAX).
Using a heart rate to predict exercise intensity:
Put the index and middle finger on top of the wrist to feel the radial pulse, or on the neck to feel the carotid pulse.
DO NOT USE THUMB: It can generate its own pulse and one might miss their beat.
A way of measuring heart rate or oxygen saturation percentage (you want to be above 95 %) while exercising is with the PULSE OXIMETER.
Heart monitors (in the form of a watch, a band underneath the nipple line, etc).
MAXIMUM HEART RATE: 220 - AGE.
RHR: RESTING HEART RATE.
THR: TRAINING HEART RATE.
RR1-5: RECOVERY HEART RATE in the 5 minutes that follow exercise. Take your heart rate every min after exercise, for five minutes. The sooner one can get back to the resting heart rate, the fitter one is. It implies a bigger and stronger heart. It implies that the vessels are healthier and therefore the oxygen demand is less required in the muscles. Quicker, because it can be supplied by the heart faster in the recovery.
THE KARVONEN METHOD: A trained athlete will have a lower resting heart rate, due to the relationship between stroke volume, heart rate and cardiac output. For example, if you are 20 and your resting heart rate is lower than someone else your age, your Karvonen method target zone will be slightly lower, meaning they should be able to perform at that intensity for longer.
220 - 20 = 200. Both of the 20 year old’s maximum heart rate is 200. But they have different fitness levels. The fitter one has a lower resting heart rate.
Guy 1: Resting heart rate of 60.
220-20 = 200 MAX HR.
200-60 = 140.
Multiply 140 by the exercise intensity: 140 x 0.8 (80 %) = 112.
112 + resting HR: 112 + 60 = 172.
This performer’s 80 % anaerobic threshold will be 172 bpm. Have 28 bpm left till maximum heart rate.
Guy 2: Resting heart rate of 50.
220-20 = 200 MAX HR.
200-50 = 150.
150 x 0.8 = 120.
120 + 50 = 170.
This performer’s 80 % anaerobic threshold will be 170 bpm. Have 30 bpm left till maximum heart rate.
If one asks these two guys to work at the same beats per minute, the unfit will have more trouble maintaining it.
PERCEPTION:
THE BORG SCALE: Scale out of 20. 7: Very, very light work. 20: Extremely hard. This is not technical. Not about heart rate, but about how hard you think you are working. Each person has different thresholds. Perception is different. For some people, certain exercise would qualify as a 10 / 20, and for others with a lower anaerobic threshold or higher resting heart rate, a 17 / 20. But it is a way of tracking effort… Another disadvantage is that people could like, trying to be too proud, etc.
THE OMNI SCALE: Scale is out of 10. Not as accurate as the BORG scale, because it has less options to have variance within performance.
THE CERT SCALE: Scale is out of 10 and is for children. Levels of intensity are slightly different.
EXERCISE HEART RATE ZONES
MODERATE ACTIVITY: A maintenance / warm-up zone and it is up to 60 % of the heart rate maximum. One is not going to get fitter in this zone, but it is a nice way to warm up without over stressing the muscles too quickly. Great if one is injured, too, for maintenance. Reversibility is not going to kick in as much. Underwater running or walking, for instance.
WEIGHT CONTROL: Fitness / Fat burn. 60-70 % of the heart rate maximum. Going uphill on a treadmill, going for long distance walking, and light jogging. Low level exercise, fat is going to be the main source of energy. But one is not going to get fitter.
To get fitter, one has to be hitting really high end sixty percent, seventy percent plus, and that is the AEROBIC (Cardio training / Endurance). The higher in this zone, the fitter. 70-80 %.
ANAEROBIC (Hardcore training). Over 80 %. Training without oxygen. One cannot maintain this for long, so this is where interval training or hit training is really good, because one can get into the training zone, and back out, and back into it.
VO2 MAX (Maximum effort). Specially for elite athletes. Above 90 %.
These percentages are different, depending on the individual, sex, fitness, body size, etc. And they can change. The more one trains, the higher up these percentages go. This is important, because if you manage to get the aerobic threshold above 80 %, for example 90 %, one can be at like 83 % for a longer time. This is what elite endurance athletes have. Their anaerobic threshold is high eighties, or even ninety percent. One elite athlete may run at a certain speed on the treadmill for 10km, other people would try it and they would last like 10 seconds, because either the legs give away or the heart cannot provide any more oxygen and they just hit lactic acid so quick one cannot maintain it. This is because elite athletes have a higher anaerobic threshold. Therefore, they can use oxygen at a much higher intensity for much longer.
Differences between the concepts of health-related fitness and performance-related fitness
HEALTH: BODY COMPOSITION, CV ENDURANCE, FLEXIBILITY, MUSCULAR ENDURANCE, MUSCULAR STRENGTH.
SKILL: AGILITY, BALANCE, COORDINATION, POWER, REACTION TIME, SPEED.
ABC PRS.
Health related: Body composition
BODY COMPOSITION: Percentage of body mass made up of fat, muscle and bone. Differs depending on sport and position. Health consideration: To have less body fat. Body types:
ECTOMORPH: Narrow hips, narrow shoulders, very slight frame. A distance runner, for instance.
MESOMORPH: Narrow hips, broad shoulders through muscular development. Usually refers to a muscly position or muscley athlete, such as a boxer, a sprinter or anyone who seeks that for their position in their sport and they are a mesomorph.
ENDOMORPH: In some sports, it is required to possess excess body fat, like for SUMO wrestlers, forwards in rugby, and certain defensive positions in American football. Gain advantage when having more body fat. Wider hips than shoulders.
BMI BODY MASS INDEX: Bmi has a low accuracy and studies show a low correlation and the reasons for this is that bmi is useful if one is sedentary or if the doctor wants to know. However, it is not accurate in the world of sport, because muscle weighs more than fat. Following the bmi, a lot of elite athletes would be considered obese, based on their height and weight. Results will fluctuate depending on the time of the day, by water retention, bloating, etc. Does not identify if it is fat or muscle.
SKIN FOLD CALIPERS: Can be very accurate but it takes thousands of attempts at practicing to get the right area on the body. You have about seven or eight skinfold sites that use within sport science and you simply pinch. The more is pinched in these areas, the more body fat. Difficult to do, to set up, to administer, so low accuracy and low correlation. Dependent on human error. Results will fluctuate depending on the time of the day, by water retention, bloating, etc.
Try to always do the tests at the same time of the day to compare more properly.
HYDROSTATIC WEIGHING: Underwater there is no gravity, so the weights can be separated quite easily. But again, today, there are many machines that can electronically measure bmi much more accurately.
