That means there's no moving parts and little risk of the music skipping during a vigorous workout or other activity.

FORBES: Rio, Redesigned

The survey questioned people on the number of times they completed at least 30 minutes of moderate to vigorous activity or 60 minutes for children.

BBC: Welsh health survey: One in three take no exercise

The 2008 Physical Activity Guidelines for Americans released by the Department of Health and Human Services recommends that adults age 18 to 64 engage in at least 2.5 hours of moderate-intensity aerobic exercise (brisk walking, biking) or an hour and 15 minutes of vigorous activity (like running) each week.

CNN: Is a shorter but harder workout better?

Israeli researchers who measured more than 2, 000 men and women in 1965 and again in 1995 found that those who engaged in moderately vigorous aerobic activity, either throughout their lives or just after age 40, lost only about half as much height as those who stopped exercising in middle age or never exercised at all.

WSJ: Health Journal: Yes, You Are Getting Shorter

With advances in measuring physical activity levels, we have discovered, to our horror, that 95% of the UK population are not even doing the minimum recommended amounts of physical activity to confer even basic health benefits (30 minutes' moderate to vigorous physical activity on at least five days a week - or the equivalent).

BBC: Laziness will send us to an early grave

The CDC and the AHA recommend that adults spend a minimum of 30 minutes a day, five days a week, doing moderate-intensity exercise, or at least 20 minutes a day, 3 days a week engaged in vigorous activity.

FORBES: Brisk Walking or Running: Both Reduce Risk for Heart Disease

The take-home message is that an hour of vigorous activity every day may not be enough to compensate for our deskbound (or sofa-bound) lives.

FORBES: Hard And Fast Or Slow And Steady? Choice Of Exercise Matters To Health, Study Says