Question: I have a high-school-age son who loves football, but I worry about the safety of "two-a-day" practices. The weather is always extremely hot, and the coaches work the young people really hard. What can be done to make this type of practice safer?
Answer: Most athletes have participated in some type of training regime that is similar to the "two-a-day" practice sessions so common in football.
It would be much better for any athlete to participate in a program where fitness (and skill) is developed over a longer period of time. However, because of the demands to be successful and the limitations in terms of schedules, many coaches bypass the more reasonable approach and schedule two-a-days to accomplish a lot in a shorter time.
Because football is a fall sport, the two-a-days most often occur during the hottest part of the year, and heat-related stress is a major concern. In addition, these practices require a lot of energy, and the fatigue of this much work can increase the injury rate pretty dramatically. Two-a-days can even decrease the athlete's immune-system response to the point that sickness becomes a problem.
I'll discuss several of the major problems associated with two-a-day practices based on an article from Gatorade's Sports Science Exchange Roundtable (Vol. 10 - 1999):
Dehydration: Studies have shown that football players lose more than 12 pounds during a single practice session and as much as 24 pounds of fluid loss in a 24 hour period. Of course, this weight loss is primarily from the loss of fluid and not from the loss of fat. The actual fluid amount of study participants was about 11 quarts every 24 hours.
Of course this fluid must be replaced or dehydration occurs, which can lead to severe health consequences. Most scientists realize that replacing this much fluid also requires electrolyte replacement, particularly sodium, since electrolytes — as well as fluids — are lost in the sweating process.
Good coaches encourage constant fluid replacement before, during and after hot summer workouts. Practice sessions should be stopped regularly to allow players to replace fluids with some sort of "aid" drink.
A good technique to monitor dehydration is to require athletes to weigh in (in shorts only) before the first practice and try to maintain this weight during the workout sessions. Athletes should NOT be allowed to participate in a second session if they have lost more than 2 percent of their weight. They should be weighed after the second workout and not be allowed to leave until their weight is within 4 percent of the initial weigh-in weight.
Energy: Players will use a lot of energy, probably in the area of 5,000 kcals a day during these practice sessions. Some large players may approach 10,000 kcals a day.
Players should emphasize carbohydrates, particularly a variety of fresh vegetables, fresh fruits and fruit juices. They should have access to salads, pasta, bread and other quality foods that provide energy. They should limit fatty, fried and spicy foods. Some professionals eat four or five meals a day, including a 10 p.m. snack of fresh fruit, raw vegetables, sandwiches, whole-grain bars, trail mix and fruit juice.
It is critical to feed players some concentrated carbohydrate immediately following each workout to maintain muscle glycogen levels.
Injury/sickness: The injury rate definitely rises during two-a-days, whether athletes are in peak physical condition or not. However, those who are less trained are more susceptible to both injury and sickness, because the immune system is weakened with the large increase in work. Of course, the injury rate goes up if athletes don't get enough rest to fight the accumulating fatigue.
One of the most overlooked phases of two-a-days relates to rest and recovery. Coaches should provide time for rest. Be sure athletes do rest between sessions and insist that they get sufficient rest at night.
Garth Fisher is director of the Human Performance Research Center at Brigham Young University.