Rucking has grown significantly over recent years. This is partly due to the growth of the company GORUCK and their events and partnerships (they work with Savage Race, Hyrox, Deka, and many other events). But the question is: Should you ruck?
IT DEPENDS. For the general, healthy (not injured) population, I think rucking can be very beneficial for cross training. It will help build your lower body strength and endurance which will have some carry over for running. It also places higher demands on your energy systems and cardiovascular system as a whole - this means that walking with some extra weight might have a similar stress result as jogging (for example). However, too much rucking, or rucking with loads that are too heavy for your capabilities, can be harmful. Just like any training, Rucking can be incorporated and scaled properly so that you can reap benefits and not injuries.
I am currently finishing the Tactical Strength And Conditioning Facilitator certification from NSCA, and a significant portion of it (a few hundred pages) addresses load bearing - which is what rucking is. All of the things that you think are negative about rucking are pretty obvious - it does put additional stress on the spine and joints. The straps do put a lot of stress on the Trapezius muscles (between shoulder and neck) and can cut off circulation to the arms and hands. Stress fractures and soft tissue injuries in the legs and hips are also possible, and common (based on the military studies done and sited in the certification)(I will say, as someone with experience, that the military, in general, does a very poor job with every form of fitness in a group setting. It is then not at all surprising that many injuries result from rucking in a military setting).
HOWEVER!!! You could list off a myriad of potential injuries associated with almost every form of exercise (running, weight lifting, etc.). That doesn't mean you shouldn't do it. It simply means that you should do it properly. So let's talk about proper ruck training. (Below is a basic progression you can follow to build up your rucking weight and distance in a safe way.)
DO NOT jump into long distance rucking or rucking with heavy weight as a beginner. When I first started rucking, my main goal was to scale up in both weight and distance over time for my upcoming work, but to also stay injury free as I was still doing a lot of trail running for my Obstacle Course Racing training. In the 3 years leading up to my first time rucking, I had completed over 2,000 miles of run training (mostly on trails in the mountains). Because of that training volume, I had built up a lower body that had a lot of strength endurance. I had also been strength training for more than 10 years. My point is, I wasn't coming off the couch and jumping into it, so even if you have a background in fitness - even an extensive one - take your time progressing in rucking. You are applying stresses/forces on your body that your body is probably not used to.
12 Week Beginner Progression:
Week 1: Monday & Thursday - 10lb Weight Vest or Ruck walk for 20 minutes.
Week 2: Monday & Thursday - 10lb Weight Vest or Ruck walk for 30 minutes.
Week 3: Monday & Thursday - 15lb Weight Vest or Ruck walk for 20 minutes.
Week 4: Monday & Thursday - 15lb Weight Vest or Ruck walk for 30 minutes.
Week 5: Monday & Thursday - 20lb Weight Vest or Ruck walk for 20 minutes.
Week 6: Monday & Thursday - 20lb Weight Vest or Ruck walk for 30 minutes.
Week 7: Monday & Thursday - 25lb Weight Vest or Ruck walk for 20 minutes.
Week 8: Monday & Thursday - 25lb Weight Vest or Ruck walk for 30 minutes.
Week 9: Monday & Thursday - 30lb Weight Vest or Ruck walk for 20 minutes.
Week 10: Monday & Thursday - 30lb Weight Vest or Ruck walk for 30 minutes.
Week 11: Monday & Thursday - 30lb Weight Vest or Ruck walk for 40 minutes.
Week 12: Monday & Thursday - 30lb Weight Vest or Ruck walk for 50 minutes.
Personally (PERSONALLY), I would not recommend the general person to train with more than 40lbs for Rucking. Why do I say that? I have many hundreds of miles of rucking for work (sometimes with weight over 70lbs), and have rucked with hundreds of people doing the same. Between all of our experiences, and the experiences that have been shared with me by others who have done the same (and more), anything over 45lbs is just unnecessary stress for training; that's coming from people who are training to carry over 70lbs for dozens of hours. For the general population who are trying to reap the benefits of Rucking as a method of cross training or for whatever other reason, you will get great benefits from 30-40lbs. Again, this paragraph is my opinion and personal recommendation.
As always, much will depend on your training goals, fitness level, injury history, time availability, and more. For Rucking, your physical size will also play a part. If you are going to incorporate Rucking into your program, just be smart about implementing it. Carrying more weight than someone else doesn't make you cool, and carrying more weight than you should just sets you up for injuries.