Video of Neymar training is below. I think this was part of Neymar's rehab from the World Cup back injury. I don't speak Portuguese so I don't know what the trainer is saying, but if a picture is worth a thousand words a video must be worth some. Enough to BS about at least.
Rotation using a swiss ball- Nice exercise that works the trunk in a standing way that can teach the transverse abdominus to work as well as obliques. I would encourage Neymar to get rid of that pain face. Same goes for all athletes. A tensed face is not the sign of a peak performing athlete. The neck tightens, the upper traps tighten, and this is not what we want. Sure, sometimes it happens, but try to relax and be efficient.
Overhead squat with resistance- great selection, especially for posture in the thoracic spine. Do try this at home. It will not make you a great soccer player, but it will make you a better overall human and athlete.
Unilateral push/pull - Not a bad exercise, but people think anything where you push and pull simultaneously is magic. It's not. His shoulders are shrugged, his head is in a forward position, he is leaning forward a lot, and it looks crappy. I think this is the trainer's attempt to be fancy. Basics are the best.
Hip External Rotation is addressed with the mini band- For awhile they were the craze these mini bands, but then they kind of fell off. I like the mini bands, but I don't like how in the video they don't go to single leg work, as that is when the hip muscles really need to work properly. I also don't like that the feet are fixed and he rotates the knee in and out versus actual movement that occurs like marching, stepping, shuffling, etc.. There are a ton of exercises one can do with the mini band, including walks in all directions with different stances, double leg jumps and lands, single leg hops, jogging, etc. The trainer is correct that we want to avoid the knees buckling in, but that usually occurs in sports as the foot enters and exits ground contact. The SAID principle is being violated here. Specific Adaptations to Imposed Demands, my little snowflakes
Ab roller- great exercise. Not much to say on it other than it works well at getting the abs strong in a way that prevents back pain. It also gets people who are not used to it as sore as @$@#$@% hell as do many exercises that involve a lot of tension in stretched positions.
Side plank with leg lift and use of cable- well a lot of muscles are working. I'm surprised they are not also having him wipe his buttocks at the same time. I'm only kidding. It is a solid exercise addressing the obliques and hip abductors. But again, when there are so many things going on what is he really benefiting from? Combining exercises often leaves on being compromised.
Closing thoughts- Neymar is one of the most exciting and dynamic players on Earth. Part of what makes him great is his slight frame that allows him to move so well and glide past defenders and change directions on a dime. He is a light weight race car competing against Honda Civics and Toyota Centras. I don't think he trained to be built specifically like this, it his is genetics and metabolism. Getting stronger and continuing to gain strength and small increases in muscle mass will help him, but lets say he did get much bigger (probably not very easy for a guy like him especially with all the playing), he would not be the same player as his explosive strength and reactive strength wouldn't go as far since the mass needed to overcome would be greater.
Achieving this look is not for everyone. The key is to realize being lean and strong is the way to go and that comes in different shapes and sizes. Sometimes that means someone will be a bit thicker like Suarez, and other times very lean like Neymar. Being very lean does not always guarantee moving well either, and if you look closely at some photos of Neymar, he has a reasonably sized muscle in the right places which something I discuss at length in Soccer Strong.