Concentrated bicep curls-weight increase 

I moved up from 7 pounds weights to 10. It made a huge difference. I could really feel it and struggled with the last few. I did the other arm immediately after. I rest few no more than 30 seconds and begin my next set of 20 reps or until failure. I don't think I could do 80 like with the 7 pound weights. This is work today!💪