Tim Shaw started noticing weakness in his muscles late in 2012 while playing linebacker as a special teams captain for the Tennessee Titans. Team doctors ran test after test on him in 2013 trying to find the sports injury behind his struggles.

Nobody thought he might have ALS.

Shaw even played through the 2013 preseason with the Titans before being released in the final roster cuts. He turned 30 in March, announced his retirement and then finally being diagnosed in April.

"It's the hardest thing I've ever had to hear," Shaw said Wednesday after the Titans accepted his Ice Bucket Challenge as he watched.

"Every thought runs through your mind. But as a man, you have a choice. What are you going to do? Are you going to stand up and fight for your life, or are you going to accept what someone else tells you is reality and just fade away? And so as staggering as that news was and as shocking as it is to hear and to say, I made that choice to stand up and live life to the fullest."

Shaw credits the Ice Bucket Challenge sweeping social media with helping him go public.

He announced his diagnosis in a 25-second video posted Tuesday on the Titans' web site before pouring a bucket of ice water over his head to raise money and awareness to battle the disease. He also challenged the Titans organization, Penn State football where he played in college and its coach James Franklin and his hometown community in Livonia, Michigan.

Shaw played in 80 games in six seasons starting with Carolina (2007), Jacksonville (2008), Chicago (2009) and the Titans (2010-12). Shaw was the Titans' special teams captain in 2011 and 2012.

The Titans emptied their headquarters of every available cooler and trash bucket so they could accept the ice water challenge with the former linebacker watching the mass dousing a few steps away. Even first-year coach Ken Whisenhunt, who didn't know Shaw, poured ice water on himself.

Cornerback Jason McCourty challenged all Titans' fans to take the challenge to help raise awareness, and a handful of Shaw's former teammates talked or hugged him afterward.

"I feel very humbled, humbled to be shown that type of demonstration," Shaw said.

Left tackle Michael Roos said he had been thinking of making a donation for ALS over the past few days. After Shaw shared his diagnosis, Roos made a $1,000 donation. Roos said the cause needs money more than the ice water but he also doused himself Wednesday in recognition of his former teammate.

Asked if he worries about a correlation between playing football and ALS, Roos said he isn't sure if there is a correlation.

"There are a lot of risks in this game and you can't let anybody fool you," Roos said. "You know enough of them and know you're doing something to your body that's not good. .... No one thinks that's going to happen, but you're putting your body through a lot of stuff."

McCourty already had done the challenge and made a donation Tuesday.

"He was just here a year ago at this very moment getting ready for our third preseason game against Atlanta ...," McCourty said. "A year later, and he's fighting a whole new battle. It puts life and things in perspective."

Shaw is a man of strong faith, and he notes he never missed a game as a linebacker. He is taking the one medication approved to try and slow symptoms from ALS and plans a mission trip to help dig a well in an Amazon village in Brazil in September.

"I believe God has built this body in a way to withstand something like this and to fight something like this, so absolutely that is my No. 1 driving force," he said.

(Copyright 2014 The Associated Press. All rights reserved. This material may not be published, broadcast, rewritten or redistributed.)

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