It's the question that has long caused controversy in the fitness realm — which is superior, pull-ups or chin-ups?

According to some enthusiastic Reddit users — chin-ups are "better" than pull-ups after a debate kicked off when a Reddit user asked about the difference between the two upper-body strength exercises.

People were quick to point out the muscles the two variations train, but some argued there's no real benefit to pull-ups as chin-ups work the same muscles, if not more.

To clarify, chin-ups are a supinated or underhand grip, while pull-ups are a pronated or overhand grip.

"Chin-ups are going to involve a larger amount of muscle and are much easier to progress on weighted and progression is the key to results," one Reddit user explained.

Another agreed, adding: "Chin-ups also allow a greater range of motion when done properly because they allow the elbows to travel farther behind the back causing a greater contraction."

Others said chin ups work biceps more because it uses extra muscle mass.

"To avoid a poor ROM (range of motion) caused by people using very wide grips on pull-ups (people do this in the hopes that will hit the lats better, but that's a false belief)," said another supporter of chin ups.

The debate sparked when the Reddit user wanted clarification on why Martin Berkhan, a Swedish nutritional consultant and self-described "God of intermittent fasting" recommended chin ups in his book, The Leangains Method.

"Does anyone know why the leangains book specifies chin-ups over pull ups in the RPT chapter?" the user had asked.

Myth busted

So what's the answer?

Experts say both movements are equally as effective and when it comes to activating the lats and traps (muscles in your back) they both work.

According to Sydney-based exercise physiologist Drew Harrisberg, one is no better than the other.

"They both have their benefits," Harrisberg told news.com.au

"You work your biceps through full range of motion in chin-ups, whereas in pull-ups you're working your lats more because your biceps are at a disadvantage."

He said it has long been debated, but essentially it comes down to is your (fitness) goals, grip, and width of your hand when doing the movements.

"You can do a narrow grip pull-up which will give you very similar benefits to a narrow chin-up but the difference, and this is where it gets tricky, is how wide the hand is," he said.

"If you do a wide grip pull-up vs shoulder-width or narrow grip chin-up, then you will see some significant differences because different muscles will contribute different amounts to the lift.

"Why? When you do a chin-up you are in a position where your biceps can go through a full range of motion at the elbow joint, because your hands are facing you and your grip is narrow."

However, Harrisberg said when doing a wide grip pull-up, as your hands are in a fixed position, to get your chin over the bar your biceps will initiate and ultimately help lift you up.

"But it comes to a point when your biceps/ elbow joints are at a biomechanical disadvantaged position as it can no longer bend through full range of motion because your hands are fixed, this is when the lats are forced to work extra hard."

According to the training site TNation, you can effectively train the lats, biceps, mid, and lower traps with either the pull-up or chin-up.

"Although, a simple tweak in your pull-up or chin-up form can make far more of a difference than pronation and supination ever could," a report into the two exercises read.

"But to get the most benefit, you'll have to stick to strict pulling. One study found that there was significantly lower amounts of activity in the mid-traps, lats, and biceps during the kipping pull-up than in the other strict variations."

So there you have it — just keep doing both.