Hi Stacy
I can only speak for me, but I did S&H a total of 4 weeks, and at the end of the 3rd week I could feel noticable strength improvements, and at the end of the 4th week was when I noticed the actual physical changes (triceps and shoulders more defined).
But remember~we are all different, we lift different weights (I did not lift lower than 8lbs on any upper body exercise, and usually between 10-20 for most upper body work), and we all build muscle at a different rate. Plus I was also doing cardio 5x/week while doing S&H and adding an additional total body workout (MIS) in order to work each muscle group 2x/week.
So there are a lot of factors that make our individual results so unique! But I'll give you a sample of my rotation I used:
M- step cardio + S&H Triceps-Biceps
T- kickbox cardio + S&H Legs-Shoulders
W- hi-lo cardio + S&H Chest-Back
T- IMAX or kickbox cardio (60 min)
F- step cardio
S- MIS (using as heavy weight as possible for each segment)
S- stretch/yoga
I repeated this cycle for 4 weeks, changing around which cardio videos I used so I wouldn't get bored and to keep my body guessing.
If you don't "SEE" results at the end of your rotation, don't dispair! The results will come in their own time and in their own way.
You might want to post your routine for others to see, many times we don't see the lapses and someone else may be able to point out something that you didn't know or see yourself.
Also, how long have you been lifting the weight you're using for each exercise? Maybe it's time to challenge your muscles with a heavier weight. Something that works for me when I need to increase weight for an exercise is to do the first set with the heavier weight I want to move up to, and then if I struggle too much on that first set, drop down to the next lightest weight to complete the other 1 or 2 sets. I build up to the higher weight slowly and safely, it may take a week or two, but hey, I get there!
Sorry I got so long winded
Hope I helped
Donna