Random: "I'm just saying, Hiccup Haddock wouldn't be muscular."
Me: *cracks knuckles and puts on glasses* Let's do this shit.
As we all probably know, the more nutrients and the better food you get when you are a child the more fit and taller you will grow as an adult. Usually. Now looking at How To Train Your Dragon, consider that Hiccup was very short and scrawny when Berk was still being attacked by dragons. And then once the dragons stopped attacking and the village suddenly had more food instead of it being stolen all the time, Hiccup went from scrawny and tiny to a WHOPPING SIX FOOT TWO.
And yes, that is his actual height in the last two movies.
And that is largely on relatively little sun and poor nutrients from limited amounts of grains and meats and root vegetables (plus mildew's cabbage).
Whether you have watched Race To The Edge or not, you know this little shit can fight. Good. You think you gain that sort of technique by not living sparring ring?
While Hiccup is definitely more strategic in his fighting style as opposed to people like Astrid and Heather (who are both distinctly heavy-handed imo), his strong suit is his agility. Paired up with a high proficiency with a... long range of weapons (largely leaning towards swordsmanship). One, that takes a lot of practice, two he's doing it with a prosthetic leg. Consider the amount of pain and hindrance that would cause him throughout training. He is literally disabled. He needs to work twice as hard. His pain tolerance alone would be through the roof.
Sparring-wise the constant footwork and quick directional changes would vastly improve his balance and leg strength, while wielding a sword would build his shoulder, arm, and core muscles. The constant need for precise strikes and defensive maneuvers refines hand-eye coordination and grip strength, which would explain why he is such a good shot with things like his shield-crossbow contraption. And also sparring develops cardiovascular endurance due to the rapid movements and bursts of action, in other words - stamina. He's got plenty.
Now, here you may probably think "But his design for the Inferno is hollow. Isn't that because he can't lift a sword?"
That design was entirely afforded to him by Viggo Grimborn in Race to the Edge. It was a strategic decision.
Have you SEEN the prototype of that thing:
Like first of all that is VIOLENT. That is a serrated blade. It's meant to GUT people. (Go on and tell me Hiccup doesn't have anger issues, I dare you.)
Secondly, I'd argue that has more metal than a normal sword.
And thirdly... proof of Hiccup's physical strength can be seen in the following scenes (I wish I had GIFs, I'm sorry I do not. Those are all moments from RTTE):
Knocks Astrid off her feet during sparring.
Knocks Savage off his feet while being chased.
Catches AND STOPS an axe going for his head held by someone thrice his size.
Knocks Snotlout's tooth out with his non-dominant hand.
KNOCKS TOOTHLESS (A WHOLE DAMN DRAGON) OFF A FUCKING CLIFF BY HIMSELF.
Blacksmithing is a highly physical craft that builds strength, endurance, and coordination. Hammering hot metal requires po-wer-ful arm, shoulder, and chest muscles. Lifting and maneuvering heavy materials cannot NOT strengthen your back and stomach if you've been doing it for weeks, let alone years. Which he has.
The repetitive swinging motion of the hammer builds forearm and grip strength, which is essential for control and precision. And working in the heat of a forge is ... For one, a glorious sweaty bonus, for two, it basically serves as a sauna after an excruciating amount of physical labour. Ever wondered why people go to a sauna after a workout? The heat can help repair muscles that were damaged by exercise and it can reset your thermoregulation thresholds. In other words, hot temperatures feel less severe. And I wonder why HE of all people, would be in need of THAT.
TLDR; Blacksmithing is a FULL-BODY workout that not only builds physical resilience but also sharpens mental focus and discipline.
And Hiccup started doing it as a CHILD.
As a substitute for dragon killing.
And last but not least (in fact probably the most important).
Have you ever been on a horse? Have you ever seen equestrians? I'm really grateful to have had the privilege to ride a horse and let me tell you ... Your whole body hurts after.
The constant flexing and contracting required to stay balanced in the saddle works your core muscles like there's no tomorrow, including your abs and obliques.
-> Inner thighs and pelvic muscles.
Speaking of maintaining-your-balance-and position-while-riding... Applying strength against the saddle, effectively squeezing it with your thighs, while maintaining that rhythmic back-and-forth-and-up-and-down motion CONSTANTLY if you don't want to get flung off... yeah, it destroys your inner thighs and pelvic muscles. Can confirm you walk like a penguin afterwards. It's grueling.
-> (I'm not gonna include the posture and trunk exterior muscles here because Hiccup rides like a hunch-back, therefore those benefits would not be applicable to him, cause he's a lil' gremlin.)
And lastly, staying in that saddle is not easy, even with the right technique. You need to have built your body a certain way to keep your seat if you want to move onto galloping (much like a dancer can't go en-pointe until they've strengthened their ankles). Until then, you're stuck with trotting for weeks. And trust me it still leaves you sore.
TLDR; Horse riding can: improve your balance and coordination, increase your flexibility, burn over 400 calories per hour, serve as yet another FULL-BODY workout, and improve your reflexes.
Now change that to dragon riding.
Now change that to riding canonically the fastest, smartest, and rarest of the known species of dragons in this universe?
Just the FACT our boy wasn't done flung off in that Test Drive Scene in HTTYD 1 is a cause for a standing ovation.
Realistically, Hiccup Haddock wouldn't be a fishbone. HE WOULD NOT BE BULKY EITHER. THAT IS AN ATROCITY.
But considering all that we've listed, if you wanted to consider realistic expectations based on his levels of physical activity, nutrition, and his growth spurt in response to that, he would, at the very least, be tall as fuck, and absolutely built.
And as a bonus: Have you seen his parents? The genetics are THERE.
THAT SAID, everyone's allowed to have fun with Hiccup's design! That's just my interpretation. It does not and should not invalidate anyone else's.
I'm well aware that Hiccup Haddock is a huge representation for the disabled community. Particularly those with chronic illness, neurodiveristy and limb difference. So, I'd like to finish this off with: I simply decided to go on a deep-dive, but really it's not that deep. This was just the result of my three-hours-long hyperfixation.
We love all and any renditions of Hiccup Haddock the Third, because he is just that lovable.
If you disagree with mine, that is absolutely okay. ❤️
Thank you for coming to my TED talk.