interesting thread - i just googled it, because I've always had a fuzzy understanding of why it's good, but i wanted to better clarify my thoughts... found the following (which I've cut a smidge, but sums up my vague thoughts in a coherent way, and is along the same lines as what's been previously said);

Cardiovascular exercise on machines such as treadmills and exercise bikes burns more calories than lifting weights, so is it just a waste of gym time to add strength training to your workout?
The simple answer is no. Working your muscles as well as your heart and lungs can improve your health and help you drop a clothes size faster.

"I only exercise to lose weight and get thinner. I can burn far more calories doing light cardiovascular work than heavy lifting, shouldn't I just stick to the treadmill?"
  • While cardiovascular exercise is a great way of burning the fat, adding a little strength training to your workouts will earn you extra calories every day. You'll even be burning extra calories while you're sleeping or sitting on the couch watching Eastenders.
  • Aerobic exercise may burn a few hundred extra calories for dinner, but for every additional pound of muscle you gain, your body burns around 50 extra calories every day of the week.
  • Research has shown that regular resistance training can increase your Basal Metabolic Rate by up to 15%. So for someone burning 2000 calories per day, that's a potential 300 extra calories, more than a Mars bar, burned every single day.
  • Do not be disheartened if initially you seem to be staying at the same weight or gaining slightly.
  • Muscle weighs more per square inch than fat, so whilst your weight might not be dropping very quickly, your clothes are feeling baggier and you are seeing a healthier, slimmer and better toned you in the mirror. That's far more important than anything those nasty scales have to say, any time.


"I'm not getting any younger, shouldn't I just stick to low resistance exercise to avoid injury?"
  • No in fact building a little extra muscle can actually reduce the risk of injury.
  • Strong muscles, tendons and ligaments are much more capable of withstanding stress, and the improved flexibility gained by strength training also reduces the likelihood of pulled muscles and back pain.
  • Weight training is an excellent way of combating several symptoms we all face as we get a little older.
  • Resistance exercise can reduce bone deterioration and build bone mass, preventing osteoporosis.
  • Working your muscles can also inhibit the affects of sarcopenia, the age related loss of muscle mass, strength and function. After the age of thirty there is a loss of 3-5% of muscle mass per decade, making day to day tasks gradually harder to perform and slowing down metabolism - increasing the risk of weight gain.

"How can weight training make me healthier?"
Recent research has shown that weight (or resistance) training can greatly reduce a number of health risks.
It has been proven to have a positive affect on insulin resistance, resting metabolism, blood pressure, body fat and gastrointestinal transit time, factors that are linked to illnesses such as diabetes, heart disease and cancer.