Hi Pp,
1st of all kudos on your 1st video posts here, it takes a quite a bit of courage to put yourself out there for scrutiny. 2nd of all, I like your attitude, very receiving and appreciative, that will serve you well in your quest to become a better player.
Well let's start with the positives, your built and seem to have a strong athletic foundation. This is good because you can't build a house on a stack of cards. It looks like you can move well enough and You don't look like your getting tired or winded.
Ok. Here are some things that I think may help. Too be honest, you remind me a bit of myself when I was younger (a lot younger I'm 37 now) I would expend a lot of energy hitting my shots, muscling the ball and in doing so everything would get tense and tight. That tightness didn't only effect my upper body but it would spread down through to my core and into my legs. I got way with it because I was strong but I tired easily and didn't have much flow or rhythm. Results varied and shots were streaky, outrageous winners or horrible errors. Then my coach stepped in and told me I was doing it all wrong, showed me how tennis, if you let it, could be the easiest game in the world. This is attitude is something that I think will help you. To hit a tennis ball hard, you don't necessarily need to feel like your hitting the ball 'hard'. To serve an ace, you don't need to feel like you put some gargantuan effort into your arm. You don't hit a tennis ball you swing and the ball gets in the way of your racquet path...etc..etc..
So how to we make you play looser? We have to untrain your body to tense up on every shot. This starts from your grip. Your not going to be swinging the frame like a sloppy noodle though, you still need to control the racquet face. So spread your fingers out along the grip a little more. Your find it a lot easier to keep the arm and shoulder relaxed like this and still retain racquet face control. Let's start there with your groundies.
Footwork, from what I see from the video, it's not that you can't move its just that your waiting too long to react and then taking long unbalanced strides to get into positions. Too many people wait for the opponent to hit the ball to split step. That's too late. That means your still in the air while the ball is traveling across the net. Time your split to happen while the opponent is about to swing. You should be landing when you hear the thump off his strings. Second of all, your movement is suppose to be a lot like gears of a car. You start out in 1st gear, (smaller quick steps), then shift up to 4th gear (large strides) and as you get to the ball you gear back down to 1st gear (adjustment steps). You should never feel like your lunging at the ball unless it's beyond yout reach. (movement is slightly different on clay, the sliding is considered the adjustment steps).
Rhythm is the key to good movement on the court. I've seen larger folk and seemingly out of shape guys cover the court very well because they timed their split step well and had an explosive first step to the ball. This is something you need to learn. This is an old bolleteri trick but it works, it's the 'ball' 'hit' drill. Every the ball hits the ground on your side of the court your going to say 'ball'. This will get your to be in sync with receiving the ball. When your opponent strikes the ball your going to say 'hit'. At the same time your going to be landing from your split step. Eventually you'll find your body finding a tempo or rhythm between ball and hit and you'll be splitting automatically, moving and preparing for the ball.
I apologize for the very verbose response but I felt it important to give you some specific instruction and corrective measures rather then just say...errrr yer footwork sucks...
I wish you the best of luck and look forward to your next video,
Peace bro.
