Chemistry Studies in Siena 2012: Ohhhhhh Balotelli!!!

2012 Italian National Team

For the past month, a group of us have been keeping up with the Euro Cup and cheering for Italy every step of the way. The Italian national team has advanced to the finals after some impressive moves and maybe a little bit of luck in every previous game they have played. Regardless of whether they win the Euro Cup, some of the players’ names have become household (or dormhold) for us. Goalie Gianluigi Buffon, Andrea Pirlo, Mario Balotelli, and Antonio Cassano have proven to be some of the best players on the team, and by far the most popular for us (except for Anahita, who will always love “El Niño” from Spain the most).

This blog is dedicated to the Italian national soccer team, which has been the incentive for us to finish our homework early so we can go cheer alongside the Italians as we watch the quickness, cunning, and finesse that the players bring to the field.

With high-intensity sports like soccer, it is important to maintain a good diet and to stay hydrated (I’m sure you’ve heard that from your PE instructor as well as your mother). This reduces the effect of fatigue during and after a match.

The definition of fatigue is “failure to maintain the required or expected power output.” If you play sports, be it soccer, swimming, cross country, or even karate, you’ve probably experienced fatigue at some point during training.

Let’s look at the facts for soccer players. They run between 9 to 12 kilometers (~5.5 to 7.5 miles) per game, but it’s not steady or continuous. Soccer players change their activity every 4 to 6 seconds. In a single game, players perform about 220 high-speed runs and have over 1300 changes in activity. They are also at 75% of their maximal oxygen uptake throughout the game. It’s no wonder that fatigue can impede their performance throughout the 90 minutes of the game. Here are a few of the reasons why:

There is a correlation of increased potassium in muscle and fatigue, which is hypothesized to be related to a player’s anaerobic metabolism. Potassium is increased when muscle pH is lowered, and results in depolarization of muscle membrane potential and decreased force development, making it harder to perform at higher levels during a game.

Studies have shown that the first 5 minutes of the second half of a soccer game are marked by less high-intensity running than at the start of a game. This is why you always need to warm up again during halftime: lower muscle temperature results in a decrease of high-intensity performance. A decrease of only 2 degrees Celsius can cause major inhibition of performance during the beginning of the second half, but re-warming up 7 to 8 minutes before the start of the second half can prevent this.

It has also been shown that players, regardless of their skill level, have a decrease in high-intensity activity during the last 15 minutes of the game. This could be due to glycogen depletion in muscles. Muscle glycogen is a reserve source of glucose for muscle. As the body requires energy, these stores are used up. A correlation was observed between lower glycogen levels and fatigue during intermittent exercise. Glycogen is depleted the longer players are exercising, leading to fatigue by the end of a 90-minute period.

Dehydration is also a major factor. Players lose an average of 3 liters of fluid during a match, and a 1 to 2% decrease of body mass can increase core temperature and cause cardiovascular strain, which in turn induces fatigue.

You might have heard about lactic acid build up in muscles. For years both scientists and nutritionists alike have thought that a buildup of muscle lactate is connected with fatigue. While performing high intensity exercises, glucose breaks down and oxidizes to form pyruvate, which produces lactate. This is a process called gluconeogenesis. Our tissues can’t remove the lactate as fast as it is formed, so the concentration of lactate in our blood and our muscles rises. However, more recent studies have revealed that increase of muscle lactate does not contribute significantly to fatigue during a soccer game.

So, throughout a soccer game, fatigue can happen during different periods of the match for different reasons. Players must prepare well in advance with their diets, and they must stay hydrated. If fatigue sets in during a game due to unpreparedness, it could mean a slip up, an injury, or even the loss of the game.

But we all know that won’t happen to Italia.