One of the things that seems to be a big concern to a lot of players is that martial characters be "realistic". That is, whatever characters do, it should be something that a person in the real world could also do. If you have a character that can jump 10 feet into the air or lift a ton, that's wuxia. And it breaks DnD for some people. Unless, you know, those abilities are magical. In which case, there isn't a problem.
So, decided to compare and see how close 5e's nonmagical classes can compete with the real world's athletes.
First up, strength! A character can lift up to 600 pounds with 20 strength. The world record for the deadlift, however, is an impressive 1055 pounds! So round one to the real world. Note that the Totem Barbarian can go the bear path which lets him lift an impressive 1200 pounds, buuuut

That's relying on magical fuel, which is cheating.
Next up, speed! For this, let's go with the Rogue. Cunning action means that they can move and then Dash twice if they focus just on hustling. So that's a total of 90 feet over six seconds when the rogue goes into a full sprint! Since each round is six seconds long, that means our Rogue is traveling at...10.2 miles per hour. In the real world, the fastest sprint is at a healthy 27.44 miles per hour. Ouch. Round two goes to the real world. Again, there's the monk who can go extra fast, but

Again, Monks are explicitly magical in nature and so not qualified to compete. For the record though, a level 18 monk can burn their ki while dashing for an incredible 180 feet per round...which is still only 20.4mph, well short of the record.
Next up, jumping! For the high jump, with a ten foot running start, a 20 strength fighter can jump an impressive 8 foot over the ground! Meanwhile, the world record is...8 feet, 1/2 inch. So close. When it comes to the long jump, our fighter gets aided by the ever reliable Remarkable Athlete, which adds an extra five feet to their normal twenty, for a total of 25 feet. Unfortunately, in the real world athletes are even more remarkable, and the record stands at 29 feet.
What about swimming? Swimming simply halves your speed, which sounds pretty fast if you're in the water! A rogue can glide through the water at an impressive 5.1mph. But...the world record is 5.3. Nope. No good there either.
Of course, it's not all about movement and lifting. Fighters are skilled! They can use weapons just flat out better than anyone else! Well, while fighters can throw a javelin 120 (if they accept disadvantage on the check) in the real world, javelins have been thrown as far as 375 feet. Without the sharpshooter feat, a fighter is going to have Disadvantage on archery shots at a distance of more than 150 feet, but olympians compete by shooting bullseyes at targets that are 230 feet away.
So everyone can rest easy. Just because some classes can transform into giant dragons (shapechange), stomp their foot to split the ground (Earthquake), shout ZA WARUDO to stop time itself (Time Stop), or bend reality at their whim (Wish), martial characters are well within the realm of possibility from levels 1 through 20. No weeaboo wuxia nonsense here.
So, decided to compare and see how close 5e's nonmagical classes can compete with the real world's athletes.
First up, strength! A character can lift up to 600 pounds with 20 strength. The world record for the deadlift, however, is an impressive 1055 pounds! So round one to the real world. Note that the Totem Barbarian can go the bear path which lets him lift an impressive 1200 pounds, buuuut

That's relying on magical fuel, which is cheating.
Next up, speed! For this, let's go with the Rogue. Cunning action means that they can move and then Dash twice if they focus just on hustling. So that's a total of 90 feet over six seconds when the rogue goes into a full sprint! Since each round is six seconds long, that means our Rogue is traveling at...10.2 miles per hour. In the real world, the fastest sprint is at a healthy 27.44 miles per hour. Ouch. Round two goes to the real world. Again, there's the monk who can go extra fast, but

Again, Monks are explicitly magical in nature and so not qualified to compete. For the record though, a level 18 monk can burn their ki while dashing for an incredible 180 feet per round...which is still only 20.4mph, well short of the record.
Next up, jumping! For the high jump, with a ten foot running start, a 20 strength fighter can jump an impressive 8 foot over the ground! Meanwhile, the world record is...8 feet, 1/2 inch. So close. When it comes to the long jump, our fighter gets aided by the ever reliable Remarkable Athlete, which adds an extra five feet to their normal twenty, for a total of 25 feet. Unfortunately, in the real world athletes are even more remarkable, and the record stands at 29 feet.
What about swimming? Swimming simply halves your speed, which sounds pretty fast if you're in the water! A rogue can glide through the water at an impressive 5.1mph. But...the world record is 5.3. Nope. No good there either.
Of course, it's not all about movement and lifting. Fighters are skilled! They can use weapons just flat out better than anyone else! Well, while fighters can throw a javelin 120 (if they accept disadvantage on the check) in the real world, javelins have been thrown as far as 375 feet. Without the sharpshooter feat, a fighter is going to have Disadvantage on archery shots at a distance of more than 150 feet, but olympians compete by shooting bullseyes at targets that are 230 feet away.
So everyone can rest easy. Just because some classes can transform into giant dragons (shapechange), stomp their foot to split the ground (Earthquake), shout ZA WARUDO to stop time itself (Time Stop), or bend reality at their whim (Wish), martial characters are well within the realm of possibility from levels 1 through 20. No weeaboo wuxia nonsense here.