Carrying stuff in your hand while running throws off your form, you won't be as efficient and you may be running in such a way that is not natural and may lead to injurys.
Like Corple said, a small mp3 player or something that clips onto your waist would be the smart alternative
the mp3 player i have is friggin sweet. it comes with an armband, or just clip it to your belt.
heres the link take a look at it
(its the european site so you can see the 360 view/also american version only has 128mb )
but, your other question. i dont have proof of results of HIIT yet, but i did my first HIIT workout today, and it was far more grueling than any mile ive ever ran (best is 5:26/5th grade) i love to brag but it was probably more grueling cause im not as in shape as i was.
no, it doesnt stunt growth. but if improper form is used, it can cause imbalances, which can lead to poor joint/bone development. which i guess can cause a slightly stunted growth in some cases. but you wont stop growing for dam sure. ( anybody correct me if im wrong )
300 situps or crunches or both
300 pushups .. wide and close grip . 150 / 150
150 pullups ( its a slanted machine ) . so its easier than regular
run 60 minutes
is this workout good for gaining lean muscle. and losing fat. ( i already have muscle but i want it to be lean ) not big cuz my arms are big but has muscle and fat.