Hi, I'm an anonymous underage person aspiring to join the SASR. My biggest concern (apart from the static PT) is the timed 15km (9.32057 miles) ruckmarch with a 28kg (61.7294 lb) rucksack, +7kg webbing and weapon, all in no more that 2 hours and 20 minutes. How on earth do I prepare for that?! I've already started training rucking with a 10kg rucksack at my local nature reserve, but I'm not sure how the hell I'm going to survive 15kms with all that weight, considering that running is not one of my strengths. Are there any tips you could give me to help with my training?