the body fatigues at a certain pace. "During tempo runs, lactate and hydrogen ions – by-products of metabolism – are released into the muscles," says Dr Carwyn Sharp, an exercise scientist who works with NASA. The ions make the muscles acidic, eventually

to feel abnormally tired in training. I was even struggling with my easy runs and just didn't feel myself day to day. It was demoralising as the harder I tried, the worse I ran," says Dobriskey. Symptoms are wide-ranging but can include fatigue, muscle

in open water, places most of the load of propulsion on fatigue-prone arm muscles. When your hand enters closer to your head (on wide tracks) with a steeper arm angle, your hand reaches the 'catch' with your palm facing back, where hand pressure moves you

as a coach to age-group and professional athletes durability means the capacity to maintain an efficient run technique while fatigued, and the generation of power at lower overall run speeds.To achieve this we need our bodies to be efficient when

plan or progression. You put in junk miles because you can fit them in, not because they are specific to your goals. They fatigue you, but have no meaningful benefit. Remember this: it is not about finding more time to train, but using the time you do

allow your muscles to function at high intensity for long periods without fatigue – in their quadriceps muscles than those who did all their running on flat terrain. Heightened aerobic power in your quads gives you improved knee lift while running

, dehydration, heat exhaustion, constant fatigue, hypothermia.Which of the two scenarios you are likely to face depends largely on your preparation and training programme, and the theory behind every successful marathon is largely the same. The following 10

’s time for a change. Otherwise, your repetitive stride pattern will tighten the muscles and joints and make you more susceptible to injury, while your gait simply trains you to run slowly. You risk fatigue, heavy legs and probably the onset of terminal

. When the distance exceeds 10-K, you should probably switch to a sports drink that will replace burned carbohydrates as well as fluids. Again, don’t drink anything that you haven’t tried before in practice.Q: As fatigue sets in at the end of a marathon

natural.Ironman distance• Long cycle, short run: Start with a 60-80-mile cycle followed by a 20-30-minute run. This session is designed to familiarise your legs with the feeling of running after experiencing high levels of cycling fatigue. When you