The Effect of Block Versus Daily Undulating Periodization on Strength and Performance in Adolescent Football Players

Purpose: Muscle mass, strength and power are important factors for performance. To improve these characteristics, periodized resistance training is used. However, there is no consensus regarding the most effective periodization model. Therefore the purpose of this study was to compare the effects of block (BLOCK) versus daily undulating periodization (DUP) on body composition, hypertrophy, strength, performance and power in adolescent American football players. Methods: Forty-seven subjects participated in this study (M±SD age = 17±0.8 years; strength training experience = 0.93±0.99 years). Pre- and post-measurements consisted of body mass (BM), fat mass (FMkg), body fat percentage (relFM), fat-free mass (FFM), muscle mass (MM) and muscle thickness of the M. vastus lateralis (VL), M. rectus femoris (RF) and M. triceps brachii (TB), one repetition maximum (1-RM) back squat (BS) and bench press (BP), countermovement jump (CMJ), estimated peak power from vertical jump performance (Wpeak), medicine ball put (MBP) and 40 yd sprint. Subjects were randomly assigned in either the BLOCK or DUP group prior to the 12 week intervention period consisting of 3 full-body sessions per week. Results: Both groups displayed significantly higher BM (p<0.001), relFM (p=0.005), FFM (p<0.001), MM (p<0.001), RF (p<0.001), VL (p<0.001), TB (p<0.001), BS (p<0.001), BP (p<0.001), CMJ (p<0.001), Wpeak (p<0.001) and significant lower sprint times (p<0.001) following twelve weeks of resistance training with no difference between groups. Conclusions: Resistance training was effective to increase muscle mass, strength, power and performance in adolescent athletes. BLOCK and DUP affect anthropometric measures and physical performance equally.