Optimising Training and Preventing Injury
Making Every Session Count
Training harder is not always the same as training smarter. A swimmer who pushes too hard every day risks injury and burnout; one who never challenges the aerobic system will plateau. Optimising training means identifying the right intensity, at the right time of year, with the right safeguards in place. The tools for doing this — heart rate zones, one rep max calculations, seasonal planning and injury prevention strategies — turn a vague exercise routine into a precision programme.
Maximum Heart Rate and Training Zones
Before setting a training intensity, a coach needs to know the athlete’s maximum heart rate. The formula is straightforward: maximum heart rate = 220 − age. For a 16-year-old student, the calculation gives 220 − 16 = 204 beats per minute (bpm).
Training intensity is then expressed as a percentage of maximum heart rate. The aerobic training zone sits between 60 and 80% of maximum heart rate. Using the same 16-year-old: the aerobic zone runs from 0.60 × 204 = 122 bpm to 0.80 × 204 = 163 bpm. Working within this zone is sufficient to stress the aerobic system without overloading it.
For more intense work, the anaerobic training zone spans 80 to 90% of maximum heart rate. For our 16-year-old this is 163 bpm to 184 bpm. Above this threshold, the body is working too hard for aerobic respiration to supply all the energy, so anaerobic respiration (producing lactic acid) contributes increasingly. The training threshold is the minimum intensity needed to produce a training effect — broadly, this is the lower boundary of the aerobic training zone (60% of maximum heart rate).
Maximum heart rate = 220 − age. Aerobic zone: 60–80% of maximum HR. Anaerobic zone: 80–90% of maximum HR. Always show your working and include units (bpm).
One Repetition Maximum
In weight training, the one rep max is the heaviest weight a performer can lift just once with correct technique. Once known, it is used to set the training intensity for a specific fitness aim. For strength and power, the athlete trains at above 70% of their one rep max, using approximately three sets of four to eight repetitions. For muscular endurance, they train at below 70% of their one rep max, using approximately three sets of 12 to 15 repetitions.
If a rugby player’s one rep max for the bench press is 80 kg, a strength session would use a minimum of 56 kg (70% of 80 kg = 56 kg) for three sets of six repetitions. A muscular endurance session for the same player would use a maximum of 56 kg for three sets of 14 repetitions. These boundaries ensure the correct physiological stress is applied rather than guesswork.
A 17-year-old swimmer has a one rep max of 60 kg on the shoulder press. Her coach wants to programme one strength session and one muscular endurance session per week.
Strength session: 70% of 60 kg = 42 kg. She should use at least 42 kg, performing 3 sets of 4–8 reps (e.g. 45 kg for 3 × 6).
Muscular endurance session: below 70% of 60 kg = below 42 kg. She should use less than 42 kg, performing 3 sets of 12–15 reps (e.g. 30 kg for 3 × 14).
Note: in the exam, always show the formula, the substitution, the answer and the unit (kg, bpm, %, seconds). Showing working earns method marks even if the final answer is wrong.
Altitude Training
At high altitude, the air contains less oxygen per breath — the partial pressure of oxygen is lower than at sea level. This means the body’s oxygen-carrying capacity is initially reduced when an athlete trains at altitude. The body responds to this physiological stress by producing more red blood cells, increasing the volume of haemoglobin available to transport oxygen around the body. When the athlete returns to sea level, they temporarily have a higher concentration of red blood cells, which improves their aerobic performance.
Altitude training is particularly beneficial for endurance events: marathon runners, cyclists, rowers and long-distance swimmers all use altitude camps. Mo Farah famously used altitude training camps in Font Romeu and Addis Ababa as part of his preparation for world championship and Olympic events. However, altitude training has limitations: it is expensive to travel to and stay at altitude; some athletes suffer altitude sickness (nausea, headaches, fatigue) when they first arrive; and the benefits begin to reverse within a few weeks of returning to sea level. There is also the risk of over-training at altitude because the reduced oxygen makes even moderate efforts feel much harder.
At altitude, reduced oxygen triggers the body to produce more red blood cells. On returning to sea level, the athlete has increased oxygen-carrying capacity, improving aerobic endurance. This benefit is temporary and begins to reverse after a few weeks.
Seasonal Training Periods
Most competitive sports divide the year into three training seasons, allowing athletes to peak at the right time and avoid year-round fatigue.
The pre-season (preparation phase) takes place before competition begins. The emphasis is on building general aerobic fitness through higher-volume, lower-intensity work, alongside sport-specific fitness and technique work. A football player in pre-season might focus on cardiovascular endurance, muscular strength and basic skills before the league begins.
During the competition season (peak or playing season), the goal shifts from developing fitness to maintaining fitness levels and working on the specific skills and tactics needed for matches and competitions. Training volume typically decreases while intensity is maintained. A sprinter in their competition season focuses on race-pace running and technical refinement rather than heavy strength blocks.
After the season ends, the post-season (transition phase) provides the body with active recovery. Athletes engage in rest and light aerobic training to maintain a basic level of general fitness without placing stress on the musculoskeletal system. This phase prevents the worst effects of reversibility and allows physical and psychological recovery before pre-season begins again.
Preventing Injury
Injury prevention is built into every aspect of a well-designed training programme. Key strategies include: completing a thorough warm-up before exercise to increase body temperature, muscle pliability and range of movement; avoiding over-training by selecting an appropriate weight or intensity and including adequate rest between sessions; wearing appropriate clothing and footwear that supports the joints being used; using taping or bracing to support previously injured or vulnerable joints; and maintaining hydration throughout, as dehydration thickens the blood and reduces performance.
Technique matters enormously: using correct lifting technique in weight training (neutral spine, controlled descent, knees tracking over toes in squats) prevents both acute and overuse injuries. Stretches should be eased into slowly and held — never bounced — to avoid activating the stretch reflex and risking muscle tears. Finally, training type and intensity must match the training purpose: a swimmer preparing for a long-distance event should not spend every session in the anaerobic zone.
For a marathon runner, altitude training is highly beneficial: it directly increases red blood cell production, improving the oxygen supply to muscles during a race that relies entirely on aerobic respiration for 26.2 miles. The investment in travel and accommodation is justified by the performance gains. For a 100 m sprinter, altitude training offers far less benefit: the race lasts under 12 seconds and relies almost entirely on the anaerobic ATP-PCr system, not on oxygen delivery. The sprinter would be better served by plyometric training and sprint-specific interval work at sea level. This comparison shows that the same intervention can have very different values depending on the energy system demands of the sport.