I just finished a 7.627km running that lasted about 0hh:39mm:9ss !
2km of warm-up followed by speed training at threshold pace (around 170 bpm).
The training consisted of performing a short pyramidal Fartlek, 1 'fast +1' slow + 2 'fast + 2' slow + 3 'fast + 3' slow + 2 'fast + 2' slow + 1 'fast + 1' slow .
It is incredible how the body adapts to speed as you progress with this exercise.
It has gone well to feel fast and with capacities to improve.
Advice for all runners: do not limit yourself to just running long, working on speed will provide you with much more resistance than you think.
Keep on running!
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