Physiology and Physical Demands
Common running events can often be split into three categories- sprints, middle-distance and long-distance running events for both men and women. Short-distance sprint races include the 100m, 200m and 400m. Middle and long-distance events range from 800m-5000m and long distance including 10000m up to the marathon (and beyond!).
The predominant physiological factor displayed across sprinters is a high percentage of fast twitch muscle fibers (up to 75%). Fast twitch muscle fibers produce force at a high rate, allowing sprinters to generate higher power outputs. The anaerobic PC system will be predominant, in which ATP is re-synthesised at a high rate for a short period of time therefore ideally suited to meet the energy demand of sprinting. Power, technique, and sprint-specific endurance are considered key underlying determinants of 100-m sprint performance.
Middle distance runners have a high level of both speed and endurance therefore rely heavily on both the aerobic and anaerobic energy systems. Middle distance races are performed at an extremely high intensity, with 800-5,000m races performed at ∼95% to 130% of VO2max. Given these race intensities the athletes will have a high amount of developed Type IIa (fast oxidative) muscle fiber types.
Key physiological determinants of long distance events include maximal oxygen uptake (VO2max), lactate threshold and running economy. During these endurance running events the aerobic energy system will be predominant throughout the duration of the race. VO2max represents the maximum volume of oxygen the body can take-up and utilise during exercise. It is measured as millilitres of oxygen consumed per kilogram of bodyweight per minute (ml/kg/min). Elite endurance athletes have measured VO2max values between 70 and 85 ml/kg/min.
A day in the life of... an elite runner
The training schedule for elite runners varies between the distance in which the athlete competes in. However, it is common for all elite runners to incorporate a variety of different types of training 2-3 times per day including long easy runs, interval sessions, fartlek running and repetitions. In addition to strength and stretching sessions. Elite 100-m athletes perform sprint-specific training over various distances. Total volume per training session is typically ~ 2000m during the preparation period and ~ 1000m during the competition period. However, marathon runners they can run between 45-150 miles (90km-250km) per week in a training phase.
Sample Training Week for an Elite Marathon runner
|Day||Morning Session||Afternoon Session|
|Monday||12-mile run||6-mile run|
Track session: 3 w/u, 25 x 400 w/35sec rest and 400 rest after each set of 5, 4c/d
Total = 15 miles
|Wednesday||17-mile run||5-mile run|
|Thursday||14-mile run||5-mile run|
9-mile run - 9-mile tempo
(5:18, 5:09, 5:12, 5:11, 5:10, 5:13, 5:10, 5:12, 5:11), 2 c/d
Total = 20 miles
|Saturday||12-mile run||6-mile run|
Running is a weight-bearing sport therefore it is common for athletes to believe that lighter body weights = better performances, however this can result in symptoms of RED-S (relative energy deficiency in sport) leading to dramatic states of leanness and nutritional deficiencies. Elite athletes need to maintain their muscle mass and strength, losing weight can be detrimental to their athletic ability. Adequate nutrition is essential to ensure the athlete is meeting their energy needs to support both training and competition. Energy requirements will differ according to the size of the runner, their gender, training intensity and the running distance they perform usually ranging from 2000-5000 kcal per day. Carbohydrates is the main fuel source and will make up the majority of the diet for elite runners. Daily carbohydrate requirements depend on the demands of training, but in general it is recommended that elite runners consume 6-10g/kg/day. The depletion of muscle glycogen has been linked to the fatigue process, particularly in the marathon therefore it is vital the athletes use the hydration station during the race to consume carbohydrate solutions.
ACSM guidelines state that body water loss of more than 2-3% of body weight should be prevented to avoid dehydration and performance impairments, however, also warns against drinking in excess of sweat rate to prevent hyponatremia. Fluid needs vary for different athletes based on their individual sweat rates, but the aim is to start any training session or competition in a euhydrated state. To work out individual sweat rate the athletes need to compare pre/post exercise body weights in similar weather/environmental conditions at which the competition is taking place. The athletes should make sure they drink during and after training/competition alongside regularly monitoring their urine against a colour chart to ensure adequate hydration levels. It is common for runners to experience gastrointestinal discomfort particularly when competing in the heat alongside pre-race anxiety. To reduce the risk of this the athlete needs to maintain hydration alongside eating familiar well-tolerated foods.
Elite runners of all disciplines must prioritise recovery, due to the high intensity and frequency of training. Recovery meals need to incorporate sufficient carbohydrate to replenish glycogen stores and adequate protein to repair damaged muscles. Athletes should aim for large amounts of exogenous carbohydrate (1–1.5 g/kg/hr for 3 hours post session) and approx 0.3 g/kg of high-quality protein ASAP post session
Sawka, M. N., Burke, L. M., Eichner, E. R., Maughan, R. J., Montain, S. J., & Stachenfeld, N. S. (2007). American College of Sports Medicine position stand. Exercise and fluid replacement. Medicine and science in sports and exercise, 39(2), 377-390.
Thomas, D. T., Erdman, K. A., & Burke, L. M. (2016). Position of the Academy of Nutrition and Dietetics, Dietitians of Canada, and the American College of Sports Medicine: nutrition and athletic performance. Journal of the Academy of Nutrition and Dietetics, 116(3), 501-528.Elite marathon training plan: https://runnersconnect.net/elite-runner-training-schedule/