OPENING ARGUMENTS:

DEFENSE

By constantly working muscles and strengthening your tendons through intense and heavy resistance exercise, you can significantly increase your overall flexibility. Being consistently active and engaging in exercises that include multijoint movements flush the soft tissues that surround joints with blood. This helps increase your flexibility.

PROSECUTION

Lifting heavy weights without stretching first can put undue stress on your joints and increase inflammation, leading to reduced flexibility. An increase in muscle mass—the addition of bigger and denser muscles hanging off your bones—may also limit your range of motion.

EVIDENCE:

  • Performing weighted movements that use a full range of motion was just as effective at improving flexibility as a program that was focused solely on static stretching, says a 2011 study published in the Journal of Strength and Conditioning Research.
  • High-intensity strength training was shown to reduce joint pain and increase mobility, according to recent research that appeared in the Journal of Rheumatology.
  • Simply following a program that involves resistance training sans stretching was shown to increase flexibility compared with a group that did no stretching or lifting, according to a study published in 2002 in the Journal of Strength and Conditioning Research.

VERDICT:

We recommend you stretch before lifting. But even if you didn’t stretch at all, you can still improve your flexibility with strength training by itself.

SENTENCING:

Be sure to add in more functional and full-body exercises, which take your joints through a full range of motion, to your routine to ensure that you’re getting the full flexibility benefits of lifting weights. You’ll be more limber and have healthier joints and an overall improved musculoskeletal system.