Well I've got some years experience in training weights and boxing. If you want to achieve the lean & toned look like this:
Then the training has to be 50% cardiovascular like jogging, swimming or skipping rope. and the other 50% is what gives you the tight-skin definition, this is where resistance training (ie. machines or free weights) come in to play.
I'll try my best to indict you to resistance training in this paragraph, it's not really that complicated. First of all, the whole point of this training is to get your muscles tired, there are two ways to do this: 1) Rip the muscle fibres by lifting large weights in 5-8 repetitions (reps) or option 2) exhaust the muscle and ligament by lifting a lighter weight for 15-25 reps. The difference between the two is that option 1 results in more muscle mass and size, which is how males generally train. However option 2 will result in your muscles becoming more dense and compact, thus giving you a toned physique. Now if your going for option 2 then you should aim for 3 "sets" per exercise and 6-9 exercises per workout, you should take no more than a 30 second break in between sets,(your gym will likely have clocks on every wall to make this easy) so your muscles don't lose their blood flow and your heart rate stays up... Also, over-training is a clear and present danger that hinder your progress, your workout should ideally be 45 minutes long... at the most it should be an hour because any more time than that and you actually lose progress.
Now for how to actually do the exercises: There are actually hundreds of different exercises you can make up with free weights, so long as it takes effort it will strengthen your muscles but generally; they fall under five categories:
-Curling, a motion where you contract a hinge joint, meaning you bend your elbow or knee to bring your hand/foot closer to your body. Curling your arms will train your bicep and curling your legs will train your hamstring (rear-thigh) as a girl, you'd probably be more keen on leg curls, which can
only be done comfortably on a machine (usually labelled 'leg curl'
-Rowing, a motion where you pull something towards your chest.. this can be done while standing up (upright row) or bent over, the most common type is in a seated position where you pull on a cable that is suspended at a similar height as your shoulders, this is the exercise that I reckon the girl in the above picture ^^ uses frequently to achieve that lean back.muscle (proper name: Latissimus dorsi)
-Pressing, a motion where you push something away from your chest, this will mainly train your pectorals which always makes a girls chest look better and healthier. Another muscle it slightly trains is the triceps which is the back of your arm, a key area for women as this usually contains large amounts of fatty tissue, women who neglect training their arms can suffer from hideous amounts of flab in later life so I highly recommend it, but not with weights, your better off simply doing press-ups (aka push-ups)
-Squatting, this one is pretty well known and obvious as to what it trains: mainly Glutes and Quadraceps, with the help of the calves, lower back and core for stability, this exercise is a cocktail of desirable muscles for females and definitely the most common one I see women doing at the gym. Be sure to practice this with no weight first, then using bar with no weights attached and working your way up in small increments as this exercise is probably the most accident-prone I've seen
-Extending, this is just like curling, but the opposite. So you can do this with your arms and legs, however the extending motion will train the "evil-twin" muscles that you train when curling, these are known as "antagonistic muscles" because they do the exact opposite of each other. Anyway, the muscle you train in arm extensions is the tricep, again a key muscle for women. and Leg Extensions train the quadriceps, which are a grey area for women. I really like a girl with big quads but a lot of guys don't , at the end of the day it's up to you.
So now you know how to do it, but what equipment do you use?
firstly, there are 3 methods of resistance training, all with their pros and cons:
-Rubber Bands, (no joke, they're rubber and called 'resistance bands'
-Free Weights
-Machines
as your a beginner, I recommend you stay away from free weights for at least two months because the last thing you want is to have an injury. The machines are pretty straight-forwards, most of them will be labelled with instructions and a picture that shows which part of your body it trains (usually in red). All you have to do is find the part that can be pushed/pulled on and follow the instruction label... or just sit around watching people do it and copy them
be sure to adjust the seat height if it's possible as your 5'4 that might require you raising the seat on many occasions.
hope this helps... also it's really important that you keep your diet clean and consistent... try to have breakfast at the same time everyday and always have a clean meal 30 minutes to an hour after the end of your workout