I have trained more than my share of Stars from Christina Aguilera to Ozzy Ozbourne, from Mike Tyson to Ricky Hatton and from Judas Priest to Black Sabbath and my main objective, cosmetic reasons aside was to make them strong and healthy. (Not easy in the case of some who live 'Rock Star' life styles and its not just Rock stars who do that-believe me! Every so often the world of health gets some new sweetheart to rave on about the current zeitgeist or cultural trend. It varies from year to year but scientifically speaking and factually, resistance training should be everyone's priority for health. Maybe you'll use weights or machines for your workout but that's incidental. Peak muscular contractions are what you need for strong limbs and joints and that's best achieved with the heaviest weights you can handle safely and with good form. (No bouncing, cheating or ballistics of any kind)
On the vanity side of things having a strong physique is also crucial for getting toned and more importantly losing the right kind of weight, namely excess fat and water and not lean tissue.
Only weight training will improve your shape and give you that Hollywood style tight biceps and buns! All the aerobics and calisthenics in the world may improve your cardiovascular system and increase flexibility, they may even help burn a few pounds off but if you start out as a pear shape you'll end up a slightly smaller pear shape. New, improved curves will only come with progressive and intense weight training. The old wives tale that travels around the office that lifting weight will make a woman bulky as a complete nonsense.
Literally dozens of studies have been done comparing dieters who lifted weights regularly with those who did aerobic exercise for the same amount of time. Both groups consumed the same number of calories and both lost the same amount on the scales but the lifters lost pure chubby fat, while about 8 percent of the aerobicisers' drop came from valuable muscle. Now that's bad for dieting period simply because the more lean muscle you have, the more fat you burn - especially if you are exercising at the right intensity. The best way to burn fat is to use your muscles to push, pull and stretch. When people just do cardio they just send shockwaves through the body. The heart doesn't differentiate whether it's beating however many times a minute - it just understands there is a demand for oxygen and blood.
There are other changes that you and everyone else will notice: Loads more energy, improved posture, more strength, (as opposed to more muscle wastage) better pain-free joint movement, fewer colds and flu, better recovery, less stress (because you now have a real workout to channel it through!) less tiredness and greater concentration. The longer you continue your regime change, the more profound and noticeable the improvements. Long term the rewards are great too as muscle training prevents osteoporosis. That's right, only weight training helps protect your bones and prevent against fractures. For the purposes of general health, resistance work does the trick every time. It protects against injuries by building core strength for better coordination and balance. It keeps getting better. Building new lean muscle tissue is also the ultimate in anti-ageing, it will also reduce drastically the chances of serious illness such as Heart Attacks and Strokes if performed regularly and consistently."
It is also great for relaxing in its uniquely cathartic way. You can channel all of your aggression into lifting weights and when you're done you aren't interested in fighting or arguing with anyone!
Just make sure you get good instruction on technique, volume and frequency-play hard but don't overdo it!
For the final word in weight training see the link below.