Annwyn's attempt to educate noobies to fitness:
Your body is composed of muscles. These muscles are what control movement and pull the strings to your metabolism. The definition for metabolism as it concerns you is the rate at which your body uses energy from food. To lose weight your goal would be to eat less than your body is using, while to gain weight you would want to eat significantly more than your body is using.
Muscle acts as an insulant to keep your body temperature constant and is also your body's greatest source of heat. Without the constant temperature that the muscular system gives the body, ideal body temperature wouldn't be kept and the body wouldn't function. It provides protection and padding against impact.
Keeping muscle tone has a range of benefits from illness prevention, cardiovascular health, safe-guarding your joints from unnessecary stress(muscles grow back, cartilage doesn't), to keeping control of your weight.
The best way to stimulate muscle tone and prevent muscle loss with age is weight bearing exercise.
A few things that you should know before starting:
Form takes presidence over weight used and repetitions performed. Without proper form, injury is more common and effectiveness of the exercise is greatly reduced. Read up on the proper form on each exercise before attempting to perform it.
Breathing is important. A byproduct of working a muscle is carbon dioxide. By failing to exhale this acidic chemical your body can go into a state of minor to severe acidosis, in which the proteins in your body break down in response to the changes in pH. Even more important to elders, pressure built up by not breathing is transferred directly to the brain, greatly increasing the chance for stroke.
Always breathe out on the eccentric(hard) part of the exercise, and breathe in on the concentric(easy part).
Warming up is essential. Studies have consistently shown that warming up prior to weight baring exercise drastically reduces the indicense of acute and chronic injury. Furthermore warmups should be exercise specific, that is to say that you should perform a warmup for every exercise performed. An example of a warmup would be doing 30 easy repetitions of a movement with the lowest possible weight in a slow, controlled movement.
There is no such thing as spot reduction. You can't choose the spots where you want to lose fat. The body sheds fat throughout the hypodermis as it needs it for energy. To burn fat it first has to get into the bloodstream, it doesn't get burned on the spot.
There is no such thing as local generalization or compartmentalization of the muscles. Muscle fibers run the length of the entire muscle from origination to insertion. Resistance is distributed along the entirety of the muscle fibers, not focused more at one end than the other. Thus there is no such thing as upper abs or lower abs. The rectus abdominis contracts as one unit from the ribcage the the pubis. There is no such thing as a lower, inner, or outer chest. The pectoralis major can be subdivided into clavicular and sternal portions by its insertion and this the upper chest can be differentiated from the mid/lower chest. However, neither of these individual muscles can be differentiated besides that. The same is true for all muscle groups. Muscle shape is determiend by genes.
Working out isn't automatically going to make you buff. Adding muscle mass is a profession to some, because it's hard to do. Working out may increase the hardness and tone of your muscles, but muscle mass is generally determined by the amount of testosterone the body is pushing around.
Progressive overload. That is, increasing the amount of volume either in weight or repetitions at a gradual pace. You can't just do the same thing every time and expect to continue getting results. Increasing performance is key to increasing gains and maximising benefits.
Such noted, there are numerous benefits to performing weight baring exercises. Just make sure you go about it properly and safely and effectively.
Got any questions? I'm up for grabs!