For any endurance athlete preparing for a spring/summer race season, January represents the time to really begin building on your endurance base and developing your strength endurance. You should now be increasing the duration of your long, slow runs. The weekend long ‘easy’ runs should form the bedrock of your training plan and will help develop a good endurance base.

Endurance training evokes a number of physiological changes within the muscle which enable your body to adapt to the increasing training load. These changes include an increase in the density of mitochondria (the oxygen power house!) within your muscle cells, an expansion of the muscle capillary network, an increased haemoglobin content and an increase in total blood volume all of which result in an improved blood supply. Both of these changes increase the aerobic capacity of your muscle fibres, making them more efficient at processing and extracting oxygen from the blood. They become more fatigue-resistant thereby enabling you to run longer distances.

There are other metabolic changes which take place within the muscle including a slower use of muscle glycogen and blood glucose, an increase in the utilisation of fat stores for energy and less blood lactate production at a given work rate. This is really important because glycogen depletion is a major factor in the onset of fatigue, particularly in endurance exercise lasting over an hour.

Also, long duration training can also help improve thermoregulation. This is the way in which your body copes with the increasing internal body temperature that occurs during long duration exercise. These runs also cause repetitions of complex movement patterns which utilise the majority of major muscles and joints within the body. Over a prolonged period of time this may improve your running biomechanics and, along with other training interventions such as strength training, enable you to become a more economical and efficient runner.
January is a really good time to work on your strength endurance, using sessions like continuous hills or longer threshold runs. These sessions are designed to improve your lactate threshold and enable you to run at a higher percentage of your maximal aerobic capacity before your anaerobic metabolism begins to play a more significant role in energy production.

In order to provide the optimal stimulus for endurance adaptation, your long runs and low intensity training should make up approximately 80% of your overall training. The remaining 20% should be higher intensity and threshold training. Aim to do at least one of these long runs a week and ensure you gradually increase your training time/mileage by no more than 1-2 miles or approximately 10%. This will ensure that your body is able to adapt and cope with the additional challenge in a progressive manner rather than suddenly increasing the workload all at once.

About the Author:

John Feeney graduated in Sports Science from the University of Portsmouth.This really opened his eyes to elite sport and the provision of sports science support. He has since completed his MSc in Applied Exercise Physiology at the University of Brighton specialising in the management of fatigue in triathlon and environmental physiology. Having participated in and coached endurance sport for a number of years, John decided to establish a consultancy with the aim to improve athletic performance by delivering accessible sports science support. His vision is to provide a range of practical sports science solutions enabling all athletes, from novice to elite, to strive for excellence and achieve their performance goals and aspirations.