Strength Training vs Functional Training for Atletic Performance

In the world of sports performance, athletes and coaches often debate the best way to build the qualities that win games: explosive power, top end speed, jumping ability, and raw strength. Should you focus on heavy barbell lifts like squats, deadlifts, bench presses, and overhead presses? Or emphasize “functional” exercises using bands, suspension trainers, and bodyweight circuits? What about plyometrics and sprint drills that directly mimic sport movements?

A landmark 10 month randomized controlled trial on elite adolescent soccer players provides compelling evidence that cuts through much of this confusion. Published in the Journal of Strength and Conditioning Research (Keiner et al., 2022), the study compared traditional strength training, plyometric and sprint training, functional training, and a control group, all performed alongside regular soccer practice. The results were clear: traditional strength training produced the most significant improvements across key performance metrics.

The Study Setup: Real Athletes, Real-World Conditions

The researchers recruited 48 elite male youth soccer players (aged around 17–18), who were already highly trained with years of structured sport practice. These weren’t novices - gains are toughest in this population, making the findings especially relevant. Over 10 months, participants maintained their normal soccer training (4–5 sessions per week, including practices, matches, and conditioning). They were randomly assigned to one of four groups, with three intervention groups adding two 60-minute supplemental sessions per week:

Traditional Strength Training (STG): Focused on compound barbell movements like squats, deadlifts, bench presses, overhead presses, and pulling exercises.
Plyometric & Sprint Training (PSTG): Included jump training, acceleration drills, maximal sprints, and explosive movements.
Functional Training (FTG): Emphasized TRX/suspension exercises, resistance bands, bodyweight circuits, and “athletic” multi-directional work.
Control Group (CG): Continued only regular soccer training with no added supplemental sessions.

All groups trained for the same total supplemental time, ensuring a fair comparison.

Key Performance Tests

After 10 months, changes were measured in foundational athletic qualities:

Maximal strength (1RM squat)
Vertical jump height (squat jump)
Linear sprint speed (20 m)
Change of direction (COD) ability (e.g., turning right/left in agility tests)

These metrics matter in nearly every explosive sport e.g. soccer, basketball, rugby, football, hockey, and more.

The Results:

The traditional strength training group clearly outperformed all others. Athletes in this group showed the largest improvements in maximal strength, vertical jump height, linear sprint speed, and change of direction ability.

In short, players who prioritized heavy barbell lifts became stronger, faster, and more explosive than those focusing primarily on plyometrics, sprint drills, or functional training, even though all groups continued the same soccer practice.

Why Strength Training Wins: The Force Production Foundation

A key takeaway from the study aligns with long standing training principles: maximal force production underpins speed and power. Heavy strength training increases an athlete’s ability to generate force, which then transfers to sprinting, jumping, and rapid directional changes, even without extensive sport specific drills.

Many athletes assume that to get faster they must sprint more, or to jump higher they must jump more. While these drills have value, this research shows that building a strong force foundation first amplifies the effectiveness of everything else.

In sports that are not strength dominant by nature, such as soccer, tennis, or combat sports, regular practice develops skills, running capacity, and jumping exposure, but it rarely maximizes strength or muscle mass. Heavy resistance training fills that gap, improving acceleration, collision tolerance, and overall robustness.

Plyometrics and functional training are not useless. They play an important role in rate of force development, movement quality, and injury resilience. However, this study suggests they are most effective when layered on top of a solid strength base, rather than used as replacements for it.

Practical Implications: A Smarter Training Hierarchy

Prioritize a strength foundation — Progressive barbell work (e.g., squats, deadlifts, presses) yields the biggest returns.
Layer on specifics — Add plyometrics, sprints, and functional drills once strength is solid.
Maintain balance — As competition nears, keep all qualities sharp without over-relying on one.

This approach avoids the common pitfall of chasing “sport-specific” training at the expense of general strength, which can limit long-term progress.

Final Takeaway

his 10 month study reinforces what experienced coaches have long observed: traditional strength training is a high yield investment for athletic performance. It does not make athletes slower, stiffer, or less agile. On the contrary, when combined with regular sport practice, it enhances speed, power, and explosiveness.

If you are an athlete or coach in a field or court sport, it may be worth auditing your program. Is maximal strength getting the priority it deserves? With evidence this strong, heavy lifting belongs at the center of athletic development, not as an afterthought, but as the base that makes everything else better.