“It’s telltale adrenaline surge is so instant and convulsive that a blood-pressure check at that moment would bust the machine that takes it,” wrote Robert Ruark in his 1953 classic, The Old Man and the Boy.

The legendary author was referring to buck fever, a malady which can affect us all in different ways. A mild case of it is good and required–if our heart doesn’t jump and our nerves don’t rattle a bit when we see a heavy 8-pointer sneaking through the woods on a frosty November morning, then why are we out there? But a bad case of the fever, with uncontrollable shaking, heavy sweat and gasping for breath, can not only ruin a hunt, but in the extreme can be dangerous.

Buck Fever is Real

In Michigan, medical researchers fitted 25 hunters, average age 55, with heart monitors and observed them in the woods. The heart rates of those hunters who shot at and hit a buck soared as high as 118 percent of their max recommended rate.

A similar study in Wisconsin tracked 10 males with monitors. Their heart rates went from an average 78 beats per minute with no game in sight to 100 beats when they spotted a deer to 128 beats a minute when they shot at a deer, any deer, even a doe.

So yes, buck fever is real, and it’s caused by a sudden surge of the chemical adrenaline. “Adrenaline comes from the adrenal gland, above the kidney,” said Jeffrey B. Michel, MD, a cardiologist at the Texas A&M College of Medicine. “It’s a powerful stimulant that increases blood pressure, heart rate and metabolic pressure.”

Adrenaline has many advantages, but like any substance coursing through the human body, it can have side effects, including shortness of breath and tremors. “Excess adrenaline can cause high blood pressure, stroke and work the heart too hard,” said Michel.

Calm the Fever

“Hunting is supposed to be a calm, thoughtful and careful process,” Michel said. “Adrenaline is not good for being any of those things, and it’s trying to find an outlet… When you hunt, there has to be training so that there is less panic. Go out on the range and be comfortable so that it isn’t a frightening or stressful situation.”

We should all make a pledge to get more heart healthy before next deer season. The better shape we’re in, the better we’ll hunt, whether or not the buck fever hits us. The American Heart Association recommends:

  • At least 150 minutes per week of moderate-intensity aerobic activity (brisk walking, biking) or 75 minutes per week of vigorous aerobic activity (jogging, hiking hills with a backpack) or a combination of both, preferably spread throughout the week.
  • Add moderate- to high-intensity muscle-strengthening activity (resistance or weights) at least 2 days per week.
  • Spend less time sitting. Even light-intensity activity can offset some of the risks of being sedentary.
  • Gain even more benefits by being active at least 300 minutes (5 hours) per week.