To tone and tighten your arms like Hudson, do arm circles with light weights. Hold your arms in front of your body in a V-shape with two-pound weights in each hand. Do ten small circles in each direction. Focus on keeping your arms long and stretched out. Keep a little bend in your elbow to avoid joint pain. For a complete arm workout do more than one set. Continue to open your arms wider and repeat until you're at the edge of your peripheral vision then work your way back in. It should be a total of no more than 60 circles out and 60 circles in.
Two-pound hand weights, $8.92, amazon.com
"Little two-pound hand weights are always great to have around the house, even one-pound weights if you travel," says Stuart.