Danish scientists have made a detailed analyze of previous scientific researches concerning exhaustion among players during a football match. By estimating Footballers’ activity during a match (including the time of and active game and the distance covered within it) proved that exhaustion symptoms among footballers are usually visible in three phases of a match:
1) During short and intensive parts of a game (during a match)
2) At the beginning of a second half
3) In the last minutes of a game
According to the authors, direct causes of a ‘shot- time’ exhaustion that accompanies an intensive competitor’s effort are not connected with shortage of glycogen depletion in muscles or the growth of lactate concentration and muscles acidification.
They also assumed that a short- time decrease in competitors’ endurance abilities is caused by ionic homeostatic disturbances that lower activity of muscle cells.
While lowering effort abilities during the first minutes of the second half of a match is caused by a drop of muscle temperature during a break between the 1st and the 2nd half of a match. That is why, undertaking a reasonable efforts enables keeping correct muscle temperature and prevent effort abilities decrease after a break.
According to the scientists, lowering glycogen level in muscle fibres is the main cause of competitors’ exhaustion in the last phase of a match.
What is more, environmental factors, such as high temperature and high air humidity cause dehydration and disturbance in functioning central nervous system, causing then reinforcement of previous exhaustion syndroms among the footballers.
Mohr M., Krustrup P., Bangsbo J. (2005), ,,Fatigue in soccer: a brief review”. Journal of Sports Sciences, 23: 593–9