Age groups
The IWF recognizes four (4) age groups:

i) YOUTH: 13 – 17 years of age

ii) JUNIOR: 15 – 20 years of age

iii) SENIOR: ≥15 years of age

iv) MASTERS: ≥35 years of age

For Olympic Games and Youth Olympic Games the relevant International Olympic Committee (IOC) Rules apply.

Source: IWF.net

For World University Championships/Universiade, FISU rules apply:  Athletes must be at least 17 and less than 25 years of age on January 1st in the year of the event.

USA Weightlifting follows the rules of the IOC/IWF/FISU where applicable at domestic events. Athletes who wish to participate in the National University & Under 25 Championships must meet the age criteria set out by FISU above.