Aside from a documented deficiency as Kel mentioned, all a teenager needs is a quality diet composed of decent macros, lots of water (ditch the carbonated beverages), repetition of basic compound movements and accessory drills that support his sport. Those things and good sleep hygiene are the building blocks.
There are 3 loves in my life: my wife, my English mastiffs, and my weightlifting....Man, my wife gets really pissed when I get the 3 confused...
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