Table 1.

Inclusion and exclusion criteria according to PICOS

PICOS category	Inclusion criteria	Exclusion criteria
Population	Healthy youth and youth athletes aged 6–18 years (child aged 6–12 years; adolescent aged 13–18 years)	Adults, patient groups
Intervention	Combined or sequenced resistance training for the lower limbs (e.g., plyometric training) with balance training, metastable resistance training (e.g., plyometric training on unstable ground)	Fewer than six exercise sessions, single-mode balance or resistance training if not used as a comparator for combined or sequenced balance and resistance training; effects of nutritional supplements; core strength training
Comparator	Active or passive control	No control group
Outcomes	Measures of muscular fitness (muscle strength, power, muscular endurance) or static and dynamic balance	No reported measures of muscular fitness or balance
Study design	Controlled trials or randomized controlled trials	Uncontrolled study