Glenn...you have my sympathies. The hard truth for now, however, is to just keep riding. You will get stronger--it's only a matter of time.

Adhere to the physiological Principle of Progression: as you give your body new & harder challenges, it will adapt to them.

• Increase the distance you ride
• Increase the time you spend on the saddle
• Increase your speed
• Increase the length of the hills you climb
• Increase the gradient of the hills you climb
• Increase the speed at which you climb the hills

You get the idea.

In all of his, though, you need to try and maintain a fast cadence. At times, you'll encounter headwinds or hills that will slow down your cadence. Again, progression: increase your cadence in these situations.

Just keep riding, and you'll get better.

(You can certainly talk detailed training plans or exercises, but at this point, I think you'd be better served just by riding.)