DEAR DR. DONOHUE: I coach a small college’s lacrosse team. I have two questions for you. We are on the East Coast and play two games on the West Coast each season. We win when we play these teams at home, but we lose when we play them at their schools. Could it be jet lag? Or could it be a sleep thing? How much sleep is recommended for a collegiate athlete? — R.M.

A: Jet lag occurs when people cross a couple of time zones. Crossing time zones in a westward direction is less of a disruption to the body than crossing the same number of time zones in an eastward direction. Your competitors are at a greater disadvantage than you are. That’s not to say that your team might not suffer from jet lag, and it might account for your losses. Can you travel a day or two earlier? We’d find out for sure. The hours of sleep required by college students, athletes or not, vary considerably from student to student. On average, high-school and college students need eight or nine hours of sleep. Few that age are able to get so much sleep. Sleep deprivation impairs athletic skills. Reaction time is much slower for a sleepy athlete. Chronically sleep-deprived athletes are slower to learn new moves and new techniques. That holds for nonathletes in the classroom also.

DEAR DR. DONOHUE: I have an argument with a teammate on our wrestling team. We’re in high school. I say weight training for a wrestler should concentrate on the arms and legs. He doesn’t agree. He thinks wrestlers shouldn’t pick one or two areas but work the entire body. I think that wastes exercise time. Who’s right? — F.L.

A: It’s a wrestler’s goal to pin an opponent’s shoulders to the mat, right? To accomplish that feat, “core” muscles are most important. Core muscles are the lower back and abdominal muscles.

The rectus abdominis muscle is the front abdominal muscle that runs from the breastbone and ribs five, six and seven to the pubic bone. Routine abdominal exercises strengthen this muscle. One back muscle, the psoas, is another important core muscle. It runs from the lower backbones to the thigh bone. It’s involved in flexing the spine. Back-bending exercises strengthen it. Be careful. Back exercises have to be done with strict form in order not to cause a back injury.

The point is that you shouldn’t confine your exercise only to the arms and legs. You have to strengthen the entire body. You cannot neglect the core muscles.

DEAR DR. DONOHUE: When my grandson was 8, he had two seizures. He is now 15. For a while, he took medicines but hasn’t done so in three years. Can he participate in sports? How about contact sports? — J.A.

A: Children whose seizures are controlled with medicine are usually allowed to play all sports. Your grandson hasn’t had a seizure in seven years and has not taken medicine in three years. His two seizures shouldn’t be a concern. It’s always wise to check with the child’s doctor.

DEAR DR. DONOHUE: I read your column where you advised against wearing a weightlifter’s belt for too long. I thought I would pass on some information with bearing on that topic. Before World War II, Japanese army officers wore a thick, wide leather belt as part of their uniform. When captured, it was not required to take routine prisoner precautions with them. Their captors simply took their belts away. The prisoners’ back muscles were so weak that they couldn’t stand. — L.C.

A: That’s something I had never heard. Constant use of a weightlifting belt can weaken muscles, but the belt would have to be worn for very long periods of time to significantly impair them.