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Is it possible to bulk my 13 year old up?!

19 replies

Eastcoastdog · 13/04/2025 15:19

DS has not long turned 13. No signs of puberty yet and he is still small (150cm) and and pretty skinny.
It gets him down and puts him at a disadvantage in sports. He is quite strong and fast but is up against boys much bigger than him.
He eats pretty well. Not an enormous appetite but balanced. Will usually eat an adult portion of food in a restaurant.
typical day of food:
Breakfast - porridge or eggs on toast or full fat yogurt & granola
Snack -bagel
Lunch- chicken wrap, yogurt, crisps, fruit
Dinner-Spag Bol/chilli/curry/sausage & mash
snack-toast /nuts/fruit

sports most days and is rarely still.

Is he too young for protein powder?
should I add a pudding at dinner time?

Or just wait and see if he has a growth spurt in the next year or so.

OP posts:
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BoilingHotand50something · 13/04/2025 15:23

He sounds fit and healthy to be honest. Could he join a gym? I don’t know much about protein powder but it isn’t something I would think would be a good idea at such a young age.

Eastcoastdog · 13/04/2025 15:32

He’d love to join a gym but can’t til next year. He does body weight stuff at home

OP posts:
Lovelynames123 · 13/04/2025 15:50

Can he not join a council gym? My nephew, 11, goes with my dsis, and I'm sure our local one is 13+

From what I remember, 30 years ago, the boys did tend to be small and slight at 13, then suddenly they were towering above us girls. I bet he'll have a growth spurt soon, he can't be the only one. My dd is 13 and although average height she's still taller than a lot of the boys

Outofthepan · 13/04/2025 15:56

I wouldn’t worry, his diet sounds great and these things even out as they grow up.

If he’d like a pudding/sweet treat in the day then I’d probably add that but not protein powder.

Pianoaholic · 13/04/2025 15:58

My son was quite small at 13 compared to his peers, within the year he had a massive growth spurt and overtook a few of them.
He is now 16 and is about 5 9, taller than DH. We are all fairly short in our family so I doubt he'll get much taller. He also eats non stop and doesn't put on weight. Annoying!
So you never know, it could all happen suddenly. It took me by surprise when he brought a load of clothes to me and said none of them fit him anymore.

AllrightNowBaby · 13/04/2025 16:00

Maybe more protein for growth but I wouldn’t worry too much.

My Gs at 13 was smaller than his friends who were all ‘shooting up’ but suddenly he seemed to grown an inch a day and now he’s 16 and a strapping 6’2” ….

TartanMammy · 13/04/2025 16:09

You can join council gym from secondary school age here.

My 10yr old is 152cm, so I can see how this would be affecting your son. But if he's got a healthy diet, lots of protein and exercising enough then I don't think there is much you can do. We can't really control how we are built beyond diet and exercise.

My 14yr old has always been tall and he's now 185cm, but until about a year ago he was very lean and skinny, but in the last year he's really broadened out in his shoulders and chest, so it probably will come with time.

Unseenentity · 13/04/2025 16:12

He's comparing himself to peers on the most powerful performance-enhancing drug known - even if you put him on an adult-type bulking programme with high protein and resistance training he just wouldn't be able to make the gains without circulating testosterone.

Very likely he will look entirely different once puberty kicks in. You can check that he has an ok intake for calories/protein to sustain normal growth, and make sure he stays positive about exercise generally.

Eastcoastdog · 13/04/2025 16:20

Unseenentity · 13/04/2025 16:12

He's comparing himself to peers on the most powerful performance-enhancing drug known - even if you put him on an adult-type bulking programme with high protein and resistance training he just wouldn't be able to make the gains without circulating testosterone.

Very likely he will look entirely different once puberty kicks in. You can check that he has an ok intake for calories/protein to sustain normal growth, and make sure he stays positive about exercise generally.

That’s true-I hadn’t really considered it like that.
hoping that there’s a big difference by this time next year (although hopefully not in his personality alongside the growth!)

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CarpetKnees · 13/04/2025 16:43

Just wait.
People develop at different ages.
My ds was 15 before he started growing but is 6' and built like a rugby player now.

ShowOfHands · 13/04/2025 16:49

I'm a teacher and lots of 13yr olds are still tiny and a lot of the boys haven't really started puberty yet.

I have a 13yr old myself and at the beginning of this academic year, he had no signs of puberty at all. Two terms later, he has every sign going, has shot up several inches, started to bulk up a bit from being whippet thin and has a very deep voice and needs to use a razor. He's gone from a boy to a young man very quickly indeed.

I'd wait a bit and just keep encouraging him to eat well and exercise.

Darkclothes · 13/04/2025 16:49

What was his father like at that age in terms of size/puberty etc? He would normally follow a similar growth trajectory. It no signs by 14, then I'd see the GP, but he has only just turned 13 and has time to catch up.

JaninaDuszejko · 13/04/2025 16:52

The average height of a 13 year old boy is 156 cm, he's very close to that and only just turned 13. Can't believe you're asking how to bulk him up. Let him grow in his own time, provide him with lots of variety of real food in his diet, make sure he exercises enough and stop being so obsessed with trying to make him bigger. There is no achievement or virtue in being bigger than average.

Motherknowsrest · 13/04/2025 16:52

Do not give him protein powder. Just let him get a healthy diet, sensible sport and activity and plenty of fresh air and sunshine.

How tall are you and his dad, basically how tall might he end up? Sit tight, he will hit puberty before long. My son took a little longer than others, then he over took them.

Middleagedstriker · 13/04/2025 16:54

Ours all joined pure gym younger. With fake ages. As long as they know how to use the machine safely it's fine we used to go with them.

Eastcoastdog · 13/04/2025 17:31

Reassuring that others grew later and it can happen quickly! I know boys tend to be later than girls.
He’s not going to be massive as his dad is average and I’m quite short. I just don’t want him to be missing anything that could help.
I’ll have another look at the local gyms-he wouldn’t get away with a fake age because of how small he is 😆

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lizzyBennet08 · 13/04/2025 17:43

Ah it’s hard for them at this age. My nephew is around the same height and very slight at 38kg and I know that it bothers him hugely.
just reassure him that biologically he will be at least as tall as you and he has loads of growing left to do.

CheeseAndHamToastieAndCrisps · 14/04/2025 15:04

My 13 year old goes to the gym, maybe have a look at others near you.

coxesorangepippin · 16/04/2025 01:52

I'd concentrate in good protein foods: hard boiled eggs, peanut butter, lentil soups, tuna, cottage cheese.

Forget the gym, concentrate on sports instead

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