Weight training will give you strength in battle of waistline

The myths around weight training are just that — myths — and science has found the magic number of minutes to make a difference.

Just 13 minutes of regularly lifting weights has marked results.

If you avoid the weights when you visit a gym, you could be making a big mistake. Scientists believe they are among the best tools for reducing your waistline and ­improving your long-term health — and express sessions of 13 minutes could be enough to make a difference, suggests a new study published in Medicine & science in Sports & Exercise.

Researchers enlisted 34 young men who had done a little weight training but were far from your burly Zac Efron types. They prescribed the group a program of common exercises with weights three times a week, including the bench press, lateral pull-down and machine leg press, asking them to perform eight to 12 repetitions until their muscles were too tired to do any more — “lifting to failure” in gym parlance. What differed was that some were asked to perform five sets in a session of 70 minutes, some did three sets in 40 minutes and one lot did one set in just 13 minutes in the gym.

Muscle measurements after two months showed all the men were stronger, but what surprised author Brad Schoenfeld, the director of the human performance laboratory at Lehman College in New York, was that strength gains were similar in all three groups. “It looks like 13 minutes can lead to significant improvements,” he says. “Most of us can probably find that much time in our day.”

His research is the latest in a ­series of studies to bust the following myths associated with weights:

It’s easy to get injured

Not true. According to data this year from the US National Electronic Injury Surveillance System, you are likelier to get hurt on a treadmill: 36 per cent of men and women who suffered injuries in the gym did so while using a running machine, while those hurt while using weights accounted for about 4 per cent — half the number caused by skipping ropes. “In the longer term, strength training helps people to avoid injury as their balance and co-ordination improve,” says Richard Blagrove, a researcher in strength and conditioning at Birmingham City University’s school of health sciences. “And a strong body is better able to tolerate intense exercise loads as you get fitter.” Older people who lift weights have been shown to have better gaits and far fewer falls.

Cardio burns fat faster

You may think the fat-burning zone on the treadmill or exercise bike offers the swiftest route to weight loss but lifting weights — ideally together with regular cardio exercise (swimming, cycling and running) — is better because, says personal trainer Matt Roberts, it helps you to gain lean body mass and lose fat at the same time.

In a trial last year at Wake Forest University in North Carolina, 249 overweight adults who followed a calorie-restricted diet and did weight-machine workouts for 18 months lost significantly more body fat than those who walked to stay in shape.

“Surprisingly, we found that cardio workouts may actually cause older adults with obesity to lose more lean mass than dieting alone,” writes Kristen Beavers, an assistant professor of health and exercise science, who led the study.

Muscle mass drops sharply as we reach our 50s, a process called sarcopenia, and lifting weights helps to stem these losses with added benefit.

“Weight training can raise your metabolism for up to 38 hours after you finish in comparison to pure cardio, when calorie burning stops shortly after you do,” Roberts says.

It’s better to use lighter weights

Trainers such as Tracy Anderson are renowned for routines that ­require up to 100 repetitions of ­exercises with 1.4kg dumbbells. This apparently has helped to sculpt the bodies of Cameron Diaz and Gwyneth Paltrow, so it is easy to see why we may be swayed away from more hefty barbells and kettlebells.

Most experts recommend progressively heavier weights for the best results, yet a study conducted at McMaster University in Canada two years ago found size doesn’t actually matter — it’s lifting weights to exhaustion that does. Fatigue is “the great equaliser”, says Stuart Phillips, a professor of kinesiology. Take the lighter ­option if you prefer but you’ll still be in the gym when everyone else has gone home.

Bigger muscles will slow you down

Dozens of recent studies suggest weight training will probably have the opposite effect. A recent ­review of 24 studies by Blagrove, published in Sports Medicine, concluded that strength training is more “likely to provide benefits to the performance” of people who take part in endurance events such as triathlons.

It’s not just that muscles are more powerful; Blagrove discovered that strength training improves efficiency, or “running economy”, something he says could be a consequence of spring­ier tendons that lead to better stride patterns and of “neuromuscular improvements in the way the brain signals to your ­muscles”.

Only aerobic exercise boosts mood

The endorphin rush that occurs during endurance exercises such as jogging results in what has been dubbed the runner’s high. New evidence, however, suggests lifting weights is just as effective at improving your emotional wellbeing.

In May a paper from the University of Limerick looked at all 33 available studies relating to ­resistance exercise and mental health and found weight training produced “a significant reduction in depressive symptoms”.

According to Brett Gordon, a physiologist and author of the paper, which was published in the journal JAMA Psychiatry, it didn’t seem to matter if subjects hit the weights room twice or five times a week.

Lifting weights will hurt your back

A survey last year by the Chartered Society of Physiotherapy found 65 per cent of those questioned said they would avoid weight training for fear of it worsening their back pain.

Yet, says Karen Middleton, the society’s chief executive: ­“Research shows getting stronger brings a whole host of health benefits. It doesn’t mean immediately hitting the gym — to start, it can be digging in the garden or simple bodyweight exercises.”

In studies at Trinity College Dublin’s school of medicine, Fiona Wilson, an associate professor of physiotherapy, has shown that back problems are likelier to occur in people with weak back muscles than those who follow a constructive strength program at the gym.

“If someone hurts their back,” she says, “it’s not the load or the ­action of lifting that’s done the damage but the fact their back muscles are so out of condition.”

Children shouldn’t lift weights

Last year Victoria and David Beckham faced a backlash when their 12-year-old son, Cruz, was pictured on Instagram lifting weights. But Blagrove says there’s no scientific evidence that it is harmful.

“Obviously strength training needs to be progressive and you can’t ask a six-year-old to lift weights from scratch,” he says. “But beginning strength training at 16 is now considered 10 years too late.”

It’s particularly important during adolescent growth spurts, which typically occur between 10 and 15 in girls and 12 to 16 in boys. “A training stimulus such as weight training will lead to important gains in bone density at this age,” Blagrove says

First, grab a kettlebell

The weight you lift depends not on your age or body size but on your strength. Your body weight is a starting point.

“A priority is that you can do an exercise well and with good technique before you add any ­additional weight,” Blagrove says. “Once you can perform something like a squat in the right position, then you can add a medicine ball or kettlebell of an appropriate weight.”

In scientific terms, he says, you should begin by determining your “one repetition max”, or the amount of weight you can lift once only.

“About 70 to 80 per cent of that weight should constitute your starting point,” he says. “And a novice should try eight to 10 repetitions of each exercise with that weight, performing two or three sets.”

As you get stronger the weights should increase, although not too quickly.

“If you get to the point when you can lift a weight more than eight to 10 times, you need to add a little more.”

The Times