New to fixed weights in the gym

Finding myself with spare time on my hands, I have just started using fixed weights in the gym but am rather confused by my "abilities".

Any answers / advice will be very welcome

1.At home using free weights of a fixed weight I can do many more bicep than tricep reps. On the weights machines at the gym I struggle with the minimum possible for biceps (only) machine and can do 4 times more on the triceps (only) machine comfortably. Why?

2. How do I know the correct level of weight I should be using for each exercise and the correct number of reps and sets?

I should say that I:
- want to tone up and not bulk up
- am doing 8 different upper body exercises
- am doing 3 sets x 15 reps for most of them but can only manage 2 x 10 on my 2 weakest areas.

sorry to be dim!

by fixed do you mean machines? free weights are by far the best to do as you will also be using other muscles to stabalise.

If by toning up you mean losing a top layer of flab then the main thing that will help here is your eating habits - what you eat & just as importantly - when.

Squats are probably the single best weight related exercise going. I'm looking to tone too - well, add a bit of muscle for vainity reasons. So I am going on a sytem of lower reps & heavier weight - 3 sets of 8 for example. What ever you do you should change your routine every 3 weeks.

Adding muscle is unatural for the body - it wont do it if it doesn't have to so you have to shock it & stress it to make it grow. Bodybuilding.com has lots of tips & advice as well as ideas on how to split up your workout over the week. It's a pretty good site not just for muscle heads

Ixux - it's a mixture of toning upper body muscles and core muscles which are weak in addition to losing some flab!

Squats are out as I have a torn medial meniscus and am thus not doing any lower body work at all at the moment

I do some free weights at home but am trying to use the machines for variety and to make myself do it!

any other advice out there?

The gym staff ought to be able to advise you on what weights/reps/sets to do to achieve your desired results. They may also be able to explain the bi/tri difference on free and fixed weights.

I think 3x15 seems to be a fairly standard routine and seem to remember one of the trainers at my local gym saying that the weight should be such that you can feel the effort at the end of the first set but not so much that you can't complete the three sets. If 3 sets are easy increase the weight if you can't do 3 sets, decrease the weight. Having said that, I absolutely cannot do shoulder presses (extending arm vertically from shoulder to overhead) even at lowest possible weight I can only manage a total of about 2x12 no matter how hard or often I try!

In answer to question 1 - look at the pulley system on the machine. Biceps machines normally go through 2 pulley systems. Triceps normally go through 3 pulley systems. The more pulleys the easier the weight is.