HIIT Training: High-Intensity Interval Training
Nowadays, high-Intensity Interval Training (HIIT Training) is viewed as one of the most effective ways of improving the endurance capacity of the players.
How often have we been discussing the differences between men and women’s football? We can all think of lots of examples which highlight the differences between both types of football. Some examples will be in favor of women’s football and other’s will be in favor of men’s football. In this blog we will discuss research articles which explain how the differences between men and women influence their playing style.
If we take a look at football specific capacities, the difference in endurance capacity between the sexes is 12% (1). Furthermore, the kicking velocity is 18% higher in men than women, but this is less than the 33% difference in leg strength(2,3). This highlights that kicking velocity is more than just leg strength and that techniques plays an important role as well.
Looking at the most profound anthropometric difference between men and women we see that men are on average 10-15 cm taller than women(4). In Norway and the Netherlands, the average height of men is 1.82m and the tallest 2.5% of men will be taller than 1.96m(5). For women in these countries, the average length is 1.68m for which the tallest 2.5% will be around the average length of the men(5). Unlike other team sports, the rules and field dimensions in soccer are the same for men and women. Based on the just described differences between men and women, this means that the circumstances are more challenging for women than for men.
The height difference is definitely the most challenging for the goalkeepers. The average length of male goalkeeper is 78% of the bar height, whereas this is only 72% for women(1). Taken this together with the difference in leg strength, it is not surprising that female goalkeepers let more balls in over their head and on either side. Therefore, poor goalkeeping may not be the reasons of these goals, rather it is the relatively larger area that they need to defend. Furthermore, the modern football game challenges goalkeepers more and more to intercept passes. In order to do so, the goalkeeper needs to stay as far as possible from the goal to intercept the ball, whereas also taking care of not leaving the goal open for long-distance shots(1). Due to the female goalkeepers being smaller and slower, this balance is more difficult for female goalkeepers than for their male counterparts. This all contributes to the image of ‘bad goalkeeping’ in women’s football, without taking into account their disadvantageous circumstances.
Due to the lower length strength of women soccer players, they need to use a larger percentage of their maximal power to move the ball with the same speed around as men. Would they choose for this strategy, this would lead to the development of fatigue earlier in the game. This in turn, would be detrimental for the technical performance towards the end of the game. Furthermore, since they have to use a larger percentage of the maximal force, this would come at the expense of accuracy. Therefore, women opt for the same relative force as men, which results in a lower absolute force (and thus speed of the ball). However, wouldn’t we all opt for accuracy and sacrifice the speed?
Now that we have seen how the differences lead to different challenges in goalkeeping and speed of the ball, the question remains what the differences are in the activities in the field. Female players cover less total distance and less distance at higher velocities than their males counterparts(6,7). This can be explained by the lower maximal sprinting speed of women: the same absolute speed for women requires a larger percentage of their maximal capacity and is therefore physically more demanding. Looking at game statistics we see that female players experience more ball losses(7), but also score more from long-range shots(8). Women take more shots after a team-play, whereas in male soccer a shot on goal is more often preceded by an individual action(9). And finally, the conversion rate (goals per shot) is higher in female soccer than in male soccer(9), likely due to the higher saving rate of the male goalkeepers. It should be noted that most of the described differences in player data and game statistics can be explained by the natural differences between men and women as we have discussed them in this blog. This highlights the fact that we should not compare both types of football, since the circumstances are different for the sexes.
Based on the above described differences, it should be clear that we cannot compare both types of the game. If we would want to make the circumstances the same for men and women, so that we can compare both type of the game, we should let the men play on a pitch of 118 x 76m (instead of 105 x 68 m), with goals of 7.93 x 2.64m (instead of 7.32 x 2.44m), playing with a ball with the size and weight of a basketball, and a game duration of 113 min (1). Since these types of changes are not very likely to be adopted, let’s try to appreciate both types of the game on their own!
When there is a free kick, the defensive team will line up a ‘wall’ to make it more difficult the score a goal. In football the wall is placed at a distance of 9.15m from the ball. However, the height of the wall is lower in women’s football than in men’s football. This makes it easier for women to score a goal by shooting the ball over the wall. Would we want to make it as hard for women to score from a free kick as for men, the wall for women should be placed at 8.45m from the ball (or 10m for men) (1).