Just as the foams and plastic inserts in a glove can start to wear out from the impact of hundreds of pucks in practice, leg pads can get softer and even shrink in height over time. Some goalies use up to eight sets of leg pads per season.
By dedicating a set to practice, Halak makes sure the pads he wears in games have an extended shelf life.
The theory made sense to St. Louis Blues backup Jake Allen, who keeps a set of old equipment at the team's practice facility but doesn't travel with extra pads like Halak. Now on his second set of pads this season, Allen will use the first set for practices at home.
"When we're at the practice rink, I'll throw that stuff on to keep my other stuff fresh," he said.
That said, traveling with extra practice pads was a novel idea to Allen -- and most goalies.
"Nobody here ever had it before," Bruins goalie Tuukka Rask said of his playing partner's pads.
As unique as Halak's practice pads are, they weren't the only piece of practice-specific equipment uncovered while asking NHL goalies about their use of practice gloves.
Some of the extra padding was hidden -- and homemade.
Blues goalie Jordan Binnington wears what he called a "double-stuff neck guard" for practice, with additional layers of protection extended further out over his collarbone.
"Guys can shoot the puck incredibly hard nowadays, and it's almost all about protection," said Binnington, who also describes himself as a "big-time practice glove guy."
Mackenzie Blackwood is adamant about not using a practice glove to catch pucks, saying he'd rather his "hand dies" than sacrifice having the same closure and feel he wants in games, but the New Jersey Devils goalie does have a re-enforced undershirt to help protect him in practice, with extra padding sewn in over the ribs and around the collarbone and shoulders.
"I just created this monstrosity because my shoulders were getting absolutely destroyed," he said.
Blackwood is also considering making some practice-specific alterations to his current mask once he gets comfortable enough to wear his newest mask, recently received, in games.