Why Strength Gains Don’t Always Translate To Better Running Economy

Strength training can make runners stronger. Whether that strength automatically lowers the energy cost of climbing is a different question.

In a new study, twenty-five recreational runners, including 12 women, were randomized to a resistance-training group or a control group. The average participant was 34 years old. The training group completed eight weeks of exercises focused on the hip extensors, knee extensors, and ankle plantar flexors. Before and after the intervention, the researchers measured running economy and biomechanics on level ground and at 5% and 10% grades, along with muscle strength of the plantar flexors (the muscles in the feet that point the toes outward).

• Plantar-flexor strength improved after strength training. Running economy did not. The program produced no significant changes in running economy or joint biomechanics at any steepness/grade.
• Some runners did improve their economy, but those individual changes were not significantly related to changes in strength or biomechanics.

What this means for runners

Keep strength training in the program for the adaptations it reliably produces—most directly, greater force capacity. Just do not assume that a stronger calf or hip will automatically reduce the oxygen cost of running uphill within eight weeks.

If uphill performance is your goal, pair lifting with specific hill running and evaluate progress using outcomes that matter to you: sustainable climbing pace, power, perceived effort, and performance—not economy alone.

Strength gains and running gains overlap, but they are not interchangeable.