POPEYE THE Sailor Man was right to reach for a can of spinach before flexing his biceps. Spinach makes us stronger, as the cartoon character showed, turning into a tower of strength to impress his girlfriend Olive Oyl and beat off her other suitors.
Swedish researchers have discovered that nitrate found naturally in the green leafy vegetable really boosts muscle power as opposed to the earlier notion that the iron content of spinach accounted for its status as a super food.
Scientists at Stockholm’s world- famous Karolinska Institutet, who carried out tests on mice, have discovered that nitrate found in high quantities in spinach boosts the production of two proteins in the body essential to muscle strength.
In the study, the team placed nitrate directly into the drinking water of a group of mice for a week, at doses obtainable from a normal diet.
The mice given the nitrate developed significantly stronger muscles due to a increase in two proteins found naturally in the muscles and used for storing and releasing calcium, vital to making muscles contract.
While no effect could be seen in the so-called slow-twitch muscles used for moderate exercise, the scientists saw a clear change in the fast-twitch muscles used for strength and more high-intensity exercises.
Translated into human terms, consuming nitrates increases the muscle strength available for activities like lifting weights, sprinting up a steep hill and also boosts endurance.
A week into the experiment, the team examined different muscles on the legs and feet with the most dramatic effect being observed in the extensor digitorum longus muscle, which extends down the tibia and the flexor digitorum brevis muscle of the foot.
“We were rather surprised by this ‘mighty mouse’ as the muscle strength in their legs and feet had dramatically increased after seven days,” the research group leader, Dr Hakan Westerblad, said.
Late middle-aged and elderly mice were deliberately chosen. The researchers hope their findings will be most beneficial for aged people with muscle weakness and muscle diseases and help develop new treatments. The research team aims to carry out studies on humans soon.