Jen, do you have clipless pedals?
Being attached to the pedals allows us to work different muscles on the ride.  This past Sunday, I did just a little bit of riding by pulling my legs UP instead of pushing down and my glutes are STILL a little sore!  Hopefully, the gluteus maximus will be more minimus if I keep this type of pedaling up  
				
			 
			
		 
			
				
			
			
				My new biking mantra:
I am attached to my bike.  If I start to slow down, I need to unclip.  If I do not unclip, I will fall.  If I unclip, I will hurt myself less if I do fall.