"I was actually expecting it to be worse than it was from everything I was told," he said. "I guess I was preparing myself for the worst while I was out there, so when I started working out and all, it wasn't as bad getting back [as] I thought."
Something that has helped in the process is coming back at the same time as some of his teammates.
"I got back with Daniel Sorensen, Cameron Comer and Michael Alisa, and I think that's really helped me and them with getting back into shape," he explained. "All of us played together as true freshmen, and we're all good friends, so I think that's helped because we're in it together and pushing each other and all that."
Hadley was one of those true freshmen that made a very good impact during his first season, which warranted him playing time on both special teams and defense. The goal this year is to reprise that role, if not have an even bigger role within the defense.
"Spencer is doing very well," said his position coach, Paul Tidwell. "We knew he had a lot of ability before he left based on what he did here as a true freshman, and he's been looking good so far this spring, which is exciting. He can help us this year for sure."
Hadley is competing for a spot at the Buck linebacker position. Due to some minor injury issues with Brandon Ogletree, Hadley has seen first-team reps throughout this past week.
"Tree [Ogletree] is our leader and the guy that inspires all of us, so it's tough having him out, but he'll be back just fine," Hadley said. "It's given me a bit of an opportunity to show what I can do with the first team, and hopefully I'm making enough plays and showing enough effort to coaches so they get confidence in me."
Through his offseason workouts, Hadley has gained a lot of confidence in his own play. So how does he measure up currently to where he was pre-mission?
"I feel better, quicker, stronger and everything now than I ever have in my life," he said. "We maxed out on everything just before spring practice started and all my marks were better than they were before my mission, and that really gave me a lot of confidence entering spring."
Another thing that has added to his confidence is his defensive coordinator, Bronco Mendenhall.
"I absolutely love it having him coach us like he does," Hadley said. "There's not too many guys out there that can motivate like he does. He understands every aspect of the game. He knows the mental part, the physical part and how to play against what other offenses do. I couldn't think of a better defensive coordinator."
This spring has seen the advent of a lot of new drills. Some of the drills were implemented late last season, including ones that have the players jumping a heavy rope, pushing sleds and even taking a sledgehammer to large tires following most practice sessions.
"Every single drill Bronco does has a purpose," explained Hadley. "It may not look like it has much to do with football with some of them, but each one has a specific purpose for us as a well as a physical [purpose]. He makes us do each drill until we do it right, which helps us a ton. We trust everything he has us do, which is important and it will make us - it is making us - strong as a unit."
While on his mission, Hadley learned that his younger brother Matt had received an offer to play football for BYU and quickly accepted it. As one could imagine, he was pretty excited about it.
"I think everyone I met for the next month heard about it. I was so excited. I love the kid and he's such a great athlete. He definitely deserved the offer and it's going to be a blast playing with him. I wouldn't have it any other way."
Matt was only in the eighth grade when Spencer graduated, so they've never been able to compete on the same field together as teammates. That will change next season, as Matt plans to play a year before leaving for his own mission service.
"It will only be one year, but we're going to make the most of it," Hadley said. "It's a special thing for both of us and for our family. We all wish it could be for longer, but just having that one year together is something we've both looked forward to for a long time."