Hey & welcome to GT!

Originally Posted by: guitar1916I have recently started using the spider exercise from the beginner course, but my tutor mentioned that I had left it too late for any significant physical changes to my fretting hand. Is this true? Will some chords/shapes always be out of reach (no pun intended) for the older player?

As Joe correctly mentioned, as long as you don't have some physical disability, then you should be able to gradually increase your hand & finger strength & dexterity. Progress will be slower than a younger person! But with enough patience & effort it's completely normal to see progress.

Eventually it's possible that arthritis can slow you down. And that can present as early as your 40s! So you need to be careful with your hands. Work toward using the least amount of pressure & tension as possible to fret notes.

I have a few exercises aimed at improving strength & dexterity. But first always make sure you warm up with stretches!

https://www.guitartricks.com/lesson.php?input=19585

Then you'll be ready for these trill drills.

https://www.guitartricks.com/lesson.php?input=22705

And this exercise is a great way to focus on building pinky strength & dexterity.

https://www.guitartricks.com/lesson.php?input=17205

Hope that helps!