Go to the gym consistently and unfailingly, even if it’s just to walk on the treadmill for ten minutes.
Even if your legs are sore, just go.
Even if you’re not feeling it, just go.
Even if there’s that something else you’d rather be doing, just go.
Because once you’re there at the gym, you usually will get into the mood to run or achieve something more substantial.
Just do it.
Compel yourself to do just a bit of what you’re struggling to do.
Just taking action, even if you don’t plan on achieving much, can usually help you get and stay motivated.
Inertia will give way to momentum.