I am 42 yrs. old and have started a vigorous routine for the last 6 weeks. I do a full body weight training program 4 sets/15-20 reps , do 3-4 different moves per muscle group twice a week. I do 1 1/2 hours of cardio 3- 4 times a week, and take Sundays off. Im weighing heavier on the scale by approx. 8 lbs. my clothes feel tighter(legs) I eat very healthy. No sugar, no white flour, approx. 1200 cal. a day - lots of protein, veggies, salad..... anything I could be doing incorrectly? Also, Ive noticed my right arm(bi, tri and forearm) is noticably larger than my left. I am right handed, but do the same workout on each side, why does this happen? Any suggestions would be appreciated!!!

What are your stats (sex, height, weight, body fat %,...)?

It sounds like you are trying to loose body fat and teh first impression is you are probably doing too much volume and too low intensity.

Thanks for the response. I do 3-4 exercises per muscle group..... for example
shoulders, I do military press, front and side raises, shrugs and flys. I do either 4 sets of 15 or 3 sets of 20. Never use more than 12 lb. weights with free weights, machines usually between 30-50 lbs (except my legs I can do more) Im 42 yrs. old, always been athletically built, weigh approx. 140 lbs and want to lose approx 20 lbs. On my cardio days I start with 30 min of abs, 30 min on stairstepper, and 30 on the precor. I then do a cooldown on the treadmill for approx 20-30 min.
An example of my diet : breakfast: grapenuts, 2% milk and a banana
Lunch : Whole wheat tortilla wrap, turkey, cheese, lettuce, tomato, onion
(some light mayo and mustard) 1 apple
Dinner: Protein(chicken, fish or lean beef) salad, butternut squash.
Evening snack: sugar free pudding, or an orange or light yogurt
LOok forward to your input. Anxious to hear!

I use 8-12 lb weights for free weights, 30-50 on machines usually. I am 42, 5'1" and weigh 140. I would like to weigh 120-128. My body fat is around 24%
I do 1 1/2 hrs of cardio (30 min stairstepper, 30 min precor, 30 min treadmill
plus 30 min of abs on cardio day.) I lift 2 days a week (full body workout) I do many reps and the weights arent too heavy.... I am getting good definition, but weight gain on the scale? Just confused. I eat very healthy as well. any suggestions? Thanks so much!

I would cut back the aerobic training (cardio) and increase the strength training.

I suggest you click the Beginners Links in my sig.