Sand bags and TRX have been both a very valuable tool for strength and conditioning. Video below shows some basic ideas to combine too. Working with a sandbag that is attached to a TRX creates a different way to utilize some of the exercises. This is a great a great way to change up your sandbag and/or TRX routines. If you have a sandbag, TRX, kettlebell and some elastic bands this will allow you to do hundreds of exercises and you won't even need a gym membership. Some of the greatest eastern european athletes I have met used some of the simplest tools and methods to be in world class shape.
This video hits the nail with training philosophy, supplements and other facts about training regiments. I think Steve has a great point with training philosophy. We need to address range of motion, mobility issues before we can even add weight to our trainin. We also need to not blindly follow WODs that are not structured and not balanced. More than anything, like Steve says, we need to make sure what we are doing is sustainable. There are many calisthenics workouts out there people are doing that eventually catches up with them. I used to do many of these workouts when I was young with high volumes of and it eventually caught up to me. I always say I would rather be healthy and strong in my sixties going at it hard rather than being a world champion and not being able to train for rest of my life. I saw many Judo athletes that trained really hard without a structure. Over time they build up a list of injuries they suffered from serious injuries for rest of their lives. It is great to be a champion but we should not sacrifice our bodies. After all, training to most athletes is a thing they do to get a away and focus on themselves. It is a thing that most people want to cary over their lifetime and it is good to think about to future and not just the moment. I believe in training hard and peaking but just like everything in life, there should be a balance. You can still train smart and be a champion. It just takes a little more planing, effort and patience.