Beginner Weight Training

Jermski

Hey there!

So I've been doing a full-body weight training routine 3-days a week and so far have done pretty well. I just added a second set to the program today and it was really, really tough.... I mean I couldn't even do full sets of the lat pulldown, I was busted. Could I be doing something wrong? Here's my program (It's a beginners program from about.com)

Leg Press 2 sets, 12 reps, 195#
Chest Press 2 sets, 12 reps, 140#
Back Extension 2 sets, 12 reps @ 110#
Crunches 2 sets of 12 reps @ 100#
Seated Row 2 sets of 12 @ 105#
Tricep Extension 2 sets of 12 @ 95# (This was quite tough)
Lat Pulldown 1 set of 7 reps @ 85#, 1 set of 8 reps @ 85# (couldn't get all 12 reps)
Shoulder Press 2 sets of 12 @ 60# (Was very, very tough to complete)
Bicep Curl 2 sets of 12 @ 70# (Was pretty tough to complete)

Did I just wear myself out? Should I decrease the weight now that I've added a second set, or should I just continue with what I'm doing? Was it maybe just an off day, and I shouldn't worry about it?

Any help is MUCH appreciated!! Thanks!!