Eric Berry

Eric Berry's comeback from cancer was impressive right from the moment he walked through the door. After enduring a battery of chemotherapy treatments, the Chiefs safety somehow did the unthinkable: He came back to practice one pound heavier than when he left.

That slight weight gain represented an incredible achievement on Berry's part. Instead of suffering the ill-effects of cancer treatments, which usually cause weight and muscle loss, along with general weakness, Berry entered a physically brutal ordeal and came out of it without missing a beat.

Now Wall Street Journal reporters Kevin Clark and Kevin Helliker have shed some light on how Berry managed to stay in shape while fighting Hodgkin's Lymphoma. No, he didn't use performance-enhancing drugs. He simply changed his chemo regimen in a way that allowed him to maintain his football workouts.

That change: Taking his treatments through IVs, instead of the standard method that leaves a catheter in the patient's body. When the catheter is in place, patients aren't allowed to lift more than 10 pounds. Physical activity must be light, and those restrictions are in place for the duration of the chemo treatments, which can last weeks.

Eric Berry

Berry didn't want to do that -- it would disrupt his football conditioning too much. So he opted for the IV, which involves a lot of needle pricks in a short span of time, but helped better preserve his body and support his football career.

Even so, Berry's doctor says he usually advises patients to take three to six months off from intense exercise. But working out clearly didn't hinder Berry -- and in fact, it might have improved his condition.

"I think there's a physical and psychological boost from working out [during chemotherapy]," his doctor tells the Journal. "You continue your usual activities, which is good and you keep muscle mass and maintain exercise tolerance."

It also helped that Berry had a highly treatable cancer, which improved his survival odds greatly. The doctor notes that more younger individuals are opting for IV treatments because they don't interfere with their daily lives as much as the catheter method.

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