You can pack your necessary stuff in 2,5 -3,0 kgs
Here you can see the list of recommended things
For running - T-shirt, shorts, cap, socks (and 1 or 2 extra pair to change)
Shoes - Be ready for wet shoes on snow fileds, but easy in-easy out. You don´t need waterproof ones or an other extra equipment.
Weather changes - Be ready for troubles with the weather - hat and gloves, waterproof jacket and pants, down or fleece jacket
In the hut - You can wash your running shirt and tights, so have an extra t-shirt and pants to wear inside. You can use your down jacket and running pants either. You can find some indoor shoes in every hut or
Hygiene and personal stuff - small towel, toothbrush, paste, shampoo, medicaments, tapes, thats all you need.
Feeding - We have breakfasts and dinners in every hut we sleep. You can buy an extra food in huts on the way or have some energy bars in your backpack.