1. Warm-up & Cool-down
Any exercise session should follow the three stages:
Warm-up
Main activity
Cool-down
A warm-up is performed before the main activity and the cool-down is performed right at the end.
Warm-up, Cool-down, HR & Training Zones(GCSE PE: Unit 1.1.4)

2. Warm-up
A warm-up is performed before a main exercise session. It consists of three phases:
PULSE RAISER: this is any, light aerobic activity (such as jogging or side-steps) that helps to increase the bodies heart rate (HR). This increase in heart rate means more blood is sent around the body and more oxygen is delivered to the working muscles.
STRETCHING: this can either be static (standing still) or dynamic (whilst moving- eg: high knees, opening the gate, walking lunges). Stretching the muscles helps to increase the muscle temperature which reduces the risk of injury. It also helps to increase flexibility at the joints.
SKILL PRACTICE: this is where the athletes perform skills that are going to be used in their sport/game. These practices can help an athlete become mentally prepared as their co-ordination, awareness and reaction time increase.
Warm-up, Cool-down, HR & Training Zones(GCSE PE: Unit 1.1.4)

3. Cool-down
A cool-down is performed after a main exercise session. It consists of two phases:
PULSE LOWERER: this is again a light, aerobic activity (such as jogging, fast walking or side-steps). It is used to slowly bring the heart rate (HR) back down to its normal, resting level. It is also used to continue supplying the working muscles with oxygen (repaying the oxygen debt – who can remember what oxygen debt is?). It also helps to remove lactic acid and carbon dioxide.
STRETCHING: stretching in the cool-down is almost always static (standing still) and each stretch lasts around 30 seconds. Stretching at this stage helps to stop the build-up of lactic acid and prevents aching or soreness in the muscles the following day.
Warm-up, Cool-down, HR & Training Zones(GCSE PE: Unit 1.1.4)

4. Maximum Heart Rate (MHR) = 220 – Age
DEFINITION: The speed of the heartbeat measured by the number of contractions of the heart per minute (bpm). There are 4 different heart rate stages that we need to be aware of:
RESTING heart rate: the heart rate of a person who has not been subject to any recent exertion or exercise. - You do not need as much oxygen when resting so heart rate is lower. - Professional athletes have a lower resting heart rate because they are fitter and their heart does not have to work very hard at rest.
WORKING heart rate: the heart rate of a person during exercise. - the heart will beat faster when the need for oxygen is higher (the need is often high because of intense exercise or because of poor fitness levels).
RECOVERY heart rate: the rate heart when you have stopped exercising and are waiting for it to return to normal resting level. - recovery heart rate is always higher than resting heart rate. - the time it takes someone's heart rate to get back to resting level indicates a persons level of fitness – the quicker the recovery, the fitter the performer.
MAXIMUM heart rate: the highest number of beats per minute that a persons heart can reach. - A persons maximum heart rate can be calculated using the following formula:
Maximum Heart Rate (MHR) = 220 – Age

5. Target Zones Aerobic = (MHR/100) x 60 Anaerobic = (MHR/100) x 80
DEFINITION: this is a percentage area of the maximum heart rate that needs to be worked between in order to improve fitness.
There are two different target zones that we use when exercising:
Aerobic target zone: 60%-80% of maximum heart rate – improves aerobic fitness.
Anaerobic target zone: 80%-90% of maximum heart rate – improves anaerobic fitness.
. Working below 60% of maximum HR means there will be no fitness improvements
To calculate your target zones you need to use the following formulas (both include Maximum Heart Rate – which remember is related to age)
Aerobic threshold (60% of maximum heart rate):
Aerobic = (MHR/100) x 60
Anaerobic threshold (80% of maximum heart rate):
Anaerobic = (MHR/100) x 80
Warm-up, Cool-down, HR & Training Zones(GCSE PE: Unit 1.1.4)