You can also get Jennifer Lopez's arms

In a week that was not going well for the upper limb, Jennifer Lopez's gently bulging biceps were a welcome distraction from Madonna's display of sinew and road-map veins. At 40, J-Lo has pumped her arms to perfection. There is definition, but not bulk; they are slender but not scrawny.

So how does she do it?

Having given birth to twins last year, Lopez threw herself into a tough workout regime and lost 40lb in a month. Under the guidance of her trainer, Gunnar Peterson, she got up at 4am to do her three-hour daily exercise programme, which included Pilates, cardio work on the treadmill or elliptical trainer, dancing and weight training. She cut her calorie intake to under 1,400 a day. Seven months after giving birth, she completed the Malibu triathlon. On the recommendation of Peterson, she has also recently taken up suspension training, using a device that attaches to a wall or door and has stirrups for the feet or hands so that moves can be done at any angle, including upside down.

What you can do

The bicep curl is one of the exercises that Lopez includes in her weights routine. Stand up straight with feet hip-width apart. Hold a dumbbell (or bottles of water) in each hand. Flex your knees a little and make sure palms face forwards. Breathe in. As you breathe out, slowly lift the weights to shoulder level, flexing your bicep muscles as you do so to help firm them. Keep your elbows tucked in to your waist throughout. Breathe in and lower weights back down. Repeat 20 times.