Stretching is a waste of time? Arnold says that all you need to get the perfect flexibility is heavy dumbbells!

Mobility and healthy ageing are among the top priorities for Arnold Schwarzenegger, who is now in his 80s. In his recent Arnold's Pump Club newsletter, he addressed a common question: Is it really necessary to include separate stretching routines in your workout? His answer may surprise many - because strength training can improve joint flexibility on its own.

End the myth of shortened muscles

For decades, the prevailing opinion has been that strength training and flexibility go against each other. If you wanted to be more mobile, you were advised to put down the dumbbells and go stretching. This was repeated so often that most exercisers either added stretching out of obligation or quietly accepted that feeling "tight" was simply a tax on being stronger.

But Schwarzenegger looked at the scientific data. He pointed to a large meta-analysis of 36 independent studies in which researchers analyzed data from nearly 1,500 adults. The conclusion? Strength training on its own (without any added stretching programs) has been shown to improve joint flexibility.

Full range of motion as the key to success

Arnold points out that higher intensity training and, surprisingly, longer rest periods between sets have the greatest impact on improving flexibility. The most important factor, however, is the full range of motion (Full Range of Motion) under load.

It may sound surprising, but if you load the joint to its full range - which is exactly why a deep squat or controlled Romanian deadlift feels so different from partial reps - you gradually increase the muscle's tolerance to stretch.

"Muscle tension doesn't shorten you; if practiced correctly, it teaches the tissue to accept more length," Arnold explains.

So do you have to scrap stretching altogether?

"To be clear, the research doesn't argue against stretching," clarifies Schwarzenegger. "You can benefit from it, feel better after it, or simply enjoy it as part of your routine."

But the underlying message is clear: lifting weights through a full range of motion does a lot more for your mobility than you may have previously realized. If you're already training with proper technique and appropriate intensity, the flexibility you gain is a great bonus.

If you want to boost your mobility even more, stop shortening your reps and focus on performing each exercise at its maximum possible (and safe) range!