What's the general opinion on running with a weighted rucksack? I've been slowly building up my running for a couple of months now. 3 miles, half an hour's worth, three times a week. I'm not going for steady distance running but fairly intensive intervals set at 3 minutes (with a minute walking in between). As a base line fitness foundation for doing rounds of sparring basically. Recently I've added wearing a rucksack with some old handweights in it. No idea on how much it weighs (maybe 6-8kg at the most?) but I thought it would add intensity to what I already do without having to add time or distance. I'm aiming to grade for my blackbelt in October and I've heard our chief instructor is fond of impromptu runs up into the mountains to his "outdoor dojo" so I want to be prepared for such things. My idea being to run with a rucksack up until a couple of weeks before the grading and then not using it. So hopefully running without wearing it will seem much easier? Sort of like peaking for a particular week. I did my first weighted run on Saturday and after some intial shock felt it went OK. My shoulders certainly feel it. I noticed I didn't get as far round my circuit as I was obviously running slower than normal. Feel free to discuss my idea but also weighted running in general. Is it worth it? Should you mix in unweighted running too? Add weight every few weeks? Ditch it as being too stressful on the body?