All of the following resources may contain nudity, so be warned if you’re at work.
Croquis Cafe: This is a free collection of videos featuring nude models posing for 1, 2, and 5 minute intervals. The next best thing if you can’t get a real model, and you can support them to help them make more videos.
Line of Action: Timed gesture practice. Offers references for figure drawing, animals, hands and feet, and more. There’s also a ‘class mode’ that gives you longer and longer timed gestures.
Quickposes: Timed gesture practice. There are some neat challenges in here, and you can choose how much time you want for each sketch. However, do note that the overall session timer continues to tick away even if you pause on a single image!