Keep it up

According to a new poll by vitamin-supplement firm Wassen International, flagging energy levels among Brits are the key cause for lacklustre performances in the bedroom.

When asked about their New Year resolutions, one in three Brits said they wanted more sex - but 45% of respondents admitted to putting off any bedroom gymnastics with their partner due to a lack of energy. Almost 60% of respondents said they felt exhausted at least once a day - with just as many maintaining that they struggle to get out of bed in the morning. But it's our flagging "oomph" when it comes to getting into the sack that's frustrating us the most.

Clock off, then clock on

Research suggests that your energy levels reach their peak at around 5pm - so the moment you get home from work could be a much better time to get it on than last thing at night. Also, as Tracey Cox, author of Quickies advises, you can spend all day building up some sexual excitement. "Flirt with her via text or email throughout the day," says Cox. "By the time you fall through the door, you are a panting, lubricious heap of pulsating desire."

Go for a Brazilian

Never mind the food of love. If you're looking to boost your energy levels in the sack then guzzling a fruity, alcohol-free, Brazilian concoction before hand could do the trick. Acai juice - extracted from the Amazonian super berries has been found to improve blood circulation and boost energy levels.

Spoon it on

Even if your zip is flagging a little that's no reason not to have some fun at bedtime - you just need do a bit of positional tinkering, as they say in the football-management world. According to The Seven-minute Sex Secret, by Martica Heaner, some sexual positions require more energy than others. The missionary and "doggy" positions are particularly draining - burning up around 25kJs a minute apparently. However, the "spoons" position, when you lie side by side letting the mattress take the stain, requires a lot less effort.