many models don't even do runway.. i know some of the bigger ones are quitting it because of the anxiety.. runways are very scary.. no matter how many times the models walk on them they don't get too much easier to do.. the shoes can be terrifying sometimes.. and if you fall or mess up terribly..the designer may not book you again and everyone hears about it! or at least you feel like everyone is hearing about it! victoria's secret isn't really a "designer" but its runway is very well-known for the general public and heck, densel washington sits in the front row. it's extremely nerve-racking and the sequins on the catwalk mixed with the 4-inch heels make it slippery enough for any of the models to fall!
there are plenty of other things models do in their spare time, though they have some months that are much slower than others. usually there will be a brief period of no work at all but just castings to attend and then all of a sudeen BAM work work work work.. mainly catalogue/editorials/campaigns/and even test shoots. all the in-between time is full of self-mantainance, castings, and go-sees (which means a TON of walking)..and talks with the agency..attempting to eat right..working out..and figuring out where they are traveling next.. as glamourous as the image of modeling is.. its actual rating on a glamour scale is equivalent to about 2.