Daniel Murphy is back hitting for the Nationals. He says an electric current machine helped get him ready to play again. (Nick Wass/Associated Press)

ST. PETERSBURG, Fla. — When the Nationals were in Arizona in mid-May, and Daniel Murphy was still weeks away from returning to the team, a casually dressed man who didn’t belong there stood in the outfield at Chase Field and watched from a few yards away as Murphy twisted and turned through the outfield testing his knee. The man was not a coach, but Murphy seemed to be listening to him anyway, not just taking in his feedback but soliciting it. They walked off the field together, along with a few other men who stood out the way anyone who isn’t normally in the clubhouse do.

The man from whom Murphy was taking his direction was Jay Schroeder, head of EVO Ultrafit in Phoenix, the mastermind behind the electric therapy training system that Ryan Madson says revived his career. Madson is known for the black bag he brings everywhere, for wearing electric patches all over his body and sitting still while they administer pulses to his arm, legs and even head at times. The whole thing looks rather silly, though Madson swears by it. He is not the only National with a little black bag anymore.

While Murphy has yet to hook up those electrodes in public view, he, too, carries a black bag around, the same kind that holds Madson’s accelerated performance machine. Murphy had considered this kind of therapy before but only just began working with Schroeder last month.

“I’ve found it very helpful,” Murphy said. “My body feels a lot better recovering.”

Madson said he isn’t trying to push the therapy on anyone and doesn’t want to give the impression that he is. But teammates have always been curious, and some have wanted to try it out. Jayson Werth took great interest in the program when he was with the Nationals. Murphy has adopted it.

“I just want it to help him, and I think it will,” Madson said. “It’s not automatic. You have to go through a lot of work and trial and error. It’s not a magic pill. It’s just a way — I think the best way — probably the quickest, most efficient way to fix something and strengthen something that I know of. That’s legal.”

At the time Murphy worked with Schroeder, he was still testing his ability to sprint regularly. He had yet to go on the rehab assignment that eventually raised questions about his fitness and, by extension, about whether his knee would ever be the same again.

“I think it definitely helped, ” Murphy said. “I think along with the training staff and the work we were doing with them, in conjunction with using EVO, I think it produced a healthy cocktail that helped me cross the finish line.”

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