World-changing ideas summit

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The World-Changing Ideas Summit

  • BBC TV presenter Michael Mosley on the science of food and health
  • Researcher Helen Christensen on how tech can spot and treat mental health issues
  • Uber’s Kevin Corti on the hidden patterns of city transport
  • Researcher and TV presenter Emma Johnston on the impact of cities on oceans
  • Experimental architect Rachel Armstrong on interstellar travel
  • Astronauts Ron Garan and Andrew Thomas
  • + many more

On paper, it seems like a no-brainer – exercise regularly and we can look better, feel stronger and live longer.

In reality, it’s hard for many of us to muster the motivation to see it through. We may start the year with good intentions, only to find that our determination has mysteriously evaporated a few weeks later. And even if we do put in the hard work, we may not be able to see any tangible benefits, leaving us with the nagging doubt that we’ve been wasting our time with a bad regime.

While there’s no easy way to build a healthier body, science can offer some answers, revealing which strategies will bring out the best results with the least amount of effort. We’ll be exploring the science of fitness at the BBC Future’s World-Changing Ideas Summit in Sydney on 15 November. In the meantime, here are some answers to your more pressing questions.

DO I NEED TO STRETCH BEFORE I EXERCISE?

A quick pre-workout stretch certainly won’t do you any harm, but the evidence suggests it’s probably not that useful either. Three large, randomised trials all show that it won’t reduce your risk of strain or injury. Nor does it reduce the tender soreness you may feel the next morning. If you want to make the most of your time, you'd do better to start and end your session with some light aerobic exercise, which will warm up the muscles and burn some calories at the same time.

ARE WEIGHTS JUST FOR ATHLETES AND BODY-BUILDERS?

No. Although regular cardiovascular exercise is important, weight training can bring you many benefits that are not just aesthetic. Muscle can regulate your levels of insulin and blood sugar, helping you to fight type 2 diabetes, improving your overall cardiovascular health and reducing your risk of cancer.

Bulking up may be particularly important for the elderly, who are at a high risk of losing muscle and bone mass, with studies showing that regular resistance training may improve mobility and help to prevent issues like lower back pain and osteoporosis.

WHAT SUPPLEMENTS SHOULD I USE?

Health food shops are full of post-workout shakes to help your muscles recover from exertion, but a cheaper alternative may be plain old chocolate milk. It contains the perfect four-to-one ratio of carbs to protein, which helps rebuild the workout tissue, and also helps replace the electrolytes, like sodium, that are necessary for muscle contraction and which are depleted during exercise, causing cramps. And it’s tasty.

WHAT’S THE DEAL WITH ‘HIGH-INTENSITY TRAINING’?

If spending most your free time in the gym doesn’t appeal, High-Intensity Training (Hit) involves short bursts of intense exercise, amounting to only a few minutes a session. The approach does not work for everyone – there’s evidence that around 20% of people find no benefit, while 15% will make huge strides, bringing many of the same benefits as hours of conventional workouts, including improved aerobic fitness and improved insulin sensitivity. This may be due to genetic differences in the ways our cells respond to strain.

WCIS speaker Michael Mosley put the idea to the test in an article for BBC News, attempting just a few minutes of Hit a week for four weeks. The regime involved warming up on an exercise bike for a couple of minutes, and then going full throttle for 20 seconds. He then repeated the cycle once more before finishing his exercise for the week.

In another (slightly more arduous) experiment, participants trying 15 minutes of Hit a week found a 16% drop in their blood pressure and a 17% increase in the amount of oxygen in their blood – a measure of how well their heart and lungs are functioning.

Clearly, Hit isn’t for everyone, and you would should consult a doctor if you are unused to strenuous exercise, or on medication, but it may be a good alternative for people struggling to slot gym trips into their already packed schedule.

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