K 1 is too easy for most people. As long as you are not a fat man weighing more than 500 kilograms, there is basically no need to start training from k 1, because it is too simple. The only training you need to do in k 1 is to occasionally do some courses such as muscle strength perception, or you can also do some exercises to stretch and relax muscles. The rest of the formal training, it is best not to do k 1. So let's start with k2. But a lot of k2 training may make you tired, panting, and blue-faced, and novice training is more painful. That can't be helped. After all, this software is not as difficult as "k 1.5", so we can only stick to it. When you practice k2, you will feel less painful, less fierce, less painful, less short of breath and less painful than when you do k2. It's time for you to March into k3! And so on to k4! However, some training may be easier, or some muscle groups are gifted, so you can start a training directly from k3. For example, at the beginning, all my other trainings were k2, except k3 for chest muscle training. Because it is not difficult to practice a dumbbell chest muscle k3, I can only match it like this. Now my abdominal endurance is much better than before, so I practice k3 with HIIT and k4 with abdominal muscles. So it's your own soul, okay? Most training starts with k2. Whether it suits you or not, you will know it all in one training.

Come on, don't go on a diet to lose weight, and don't stay up late. Staying up late affects the fitness effect. Enriching fitness theory is more meaningful than your blind training. Now look at the articles pushed by Zhihu and keep, and your fitness theory will become more and more perfect with the passage of time.