The late Karl Gotch once said "Conditioning is the basis for all Combat Sports; go back to nature and you'll find that animals in the wild are in the greatest of shape because they use their own bodyweight and stretching", although he was mainly talking about bodyweight in general it goes far beyond that in my opinion. I have taken this literal in the way of not just developing conditioning for a sport but for life itself.
I do believe systematic exercises such as push-ups, squats, pull-ups, sit-ups, bridging and skipping rope are incredible body conditioners whether for sports or not but nothing truly beats animal movements for strengthening the body from every possible angle. The reason why that is, is because animal movements represent the natural flow of the human body's instinctive and abilities of what has been programmed into us since the dawn of man. The systematic exercises were developed during the dawn of civilization and developing cities such as worldly kingdoms of the Greeks, Romans, Britannia & even African/Indian Settlers. Animals represent power, strength, grace, natural movement and the instinctive awareness of man's original "training" system for survival throughout the cavemen era. Before the Greeks, Romans, Mongols, Cossacks & other armies of the old world, man had to survive on instinct using his body to outrun predators, swim to catch food in rivers & streams, climb trees to get food, crawl at times to sneak up on prey to feed his family, had to balance himself through rough terrain to fight off other members of tribes and had to have quick reflexes in order to survive attacks.
Animal Exercise is the ultimate old school form of exercise because it forces the body to adapt every step and it creates a chain reaction in the spinal column and teaches the instinctive nature of movement itself. Think about it, if a man in the jungle was hungry and needed to find a way to get it; he would at times need to mimic the animal's movement to get an idea of how it behaves, how it feels, being aware of predators; it developed an ingenious way of striking down an animal's instincts and outsmart it. It didn't always happen that way but because man's brain at that time was only processing information and natural instincts to fight, swim, crawl, run and balance.
Today, exercise is more concentrated, more analytical than natural and takes on a systematic approach that has become chaotic and complicated. There are literally hundreds of thousands of ways to get fit but literally only a fraction have any real benefit. You have DVD's, books, workshops & classes that teach a concentrated approach to fitness yet in today's society, natural movement is acted like a mind-boggling "new" thing yet in reality it is the oldest form of exercise not because of exercise itself but what was originally the instinctive nature of man before becoming a colonized world.
When it comes to conditioning, the animals have it made and it can teach us the greatest things on how to use our minds and our bodies to adapt every step, every turn, every possible scenario to stay within the abilities to keep going without fatiguing or have gone so far, the body doesn't know it's fatigued. You can do all the push-ups, squats, bench presses you want but you won't last very long in a bear crawl, duck walk, Monkey Jumps and other movements because they utilize every muscle in the entire system of the body and goes beyond the typical modern movement. The more you practice moving like an animal, the more you develop the muscles and joints to last in certain situations. There are systems that use animal moves in a more concentrated humanized approach such as using push-ups while moving, concentrating on using opposite arm/legs in specific movements, using yoga-esq type drills or gymnastics/breakdancing but when you truly break it down, using animal movements in the best ways possible for us humans to adapt to, can create the ultimate conditioning tool.
There are animal moves that are not meant for everyone due to either severe past injuries, bone spurs, torn ligaments and such but in the end, when we go back to being instinctive and using our bodies to crawl, walk, run, jump, climb, swing, swim and other things, we are coming to grips on what truly gives us strength, power, endurance, conditioning, coordination & agility. Animal movements give us those qualities of the human body and how we can adapt and improvise in order to become our strongest selves mentally, physically, emotionally & even spiritually.
Get your hands on incredible Animal Movements from these courses: AKC 1, AKC 2, Kids Book & Workout DVD.