A new study by researchers at Wake Forest University suggests combining weight training with a low-calorie diet preserves much needed lean muscle mass that can be lost through aerobic workouts.

The findings, "Effect of Exercise Type During Intentional Weight Loss on Body Composition in Older Adults with Obesity," appear in the November issue of the journal Obesity.

"A lot of older adults will walk as their exercise of choice," said Kristen Beavers, assistant professor of health and exercise science at Wake Forest and lead author of the study. "But this research shows that if you're worried about losing muscle, weight training can be the better option."

In this 18-month study of 249 adults in their 60s who were overweight or obese, restricting calories plus resistance training in the form of weight-machine workouts resulted in less muscle loss, but significant fat loss, when compared to weight loss plus walking or weight loss alone.

Losing weight is generally recommended for those with obesity, but preserving muscle -- while losing fat -- is particularly important for older adults in order to maximize functional benefit, Beavers said.

"Surprisingly, we found that cardio workouts may actually cause older adults with obesity to lose more lean mass than dieting alone."

Loss of lean mass could have important consequences given the high risk of physical disability among the growing population of older adults.

Time taken away from lessons for physical activity is time well spent and does not come at the cost of getting good grades, say the 24 signatories to the statement on physical activity in schools and during leisure time, published online in the British Journal of Sports Medicine.

The Statement, which distils the best available evidence on the impact of physical activity on children and young people, was drawn up by a panel of international experts with a wide range of specialisms, from the UK, Scandinavia, and North America, in Copenhagen, Denmark, in April of this year.

It includes 21 separate statements on the four themes of fitness and health; intellectual performance; engagement, motivation and wellbeing; and social inclusion, and spans structured and unstructured forms of physical activity for 6 to 18 year olds in school and during leisure time.

It says that:

• Physical activity and cardiorespiratory fitness are good for children's and young people's brain development and function as well as their intellect
• A session of physical activity before, during, and after school boosts academic prowess
• A single session of moderately energetic physical activity has immediate positive effects on brain function, intellect, and academic performance
• Mastery of basic movement boosts brain power and academic performance
• Time taken away from lessons in favour of physical activity does not come at the cost of getting good grades
  

Like anything else, weight training has its dos and don'ts, and if you want to change your physique, you should pay attention to them. Basic training principles have been established to help lifters of all levels optimize their workouts. Even so, a lot of people work out without fully understanding what these principles are and how they can be used to their fullest advantage. If all lifters (and yes, if you pick up a weight, you are a weight lifter) were to apply these simple guidelines to their training, they'd soon see radical improvements.