After living in Colorado for over 6 years now, I feel like I have a good grasp on the differences between playing tennis at sea level when I lived in Michigan, North Carolina and Hawaii compared to a mile high. I have had a number of blog readers (thank you for your feedback!) that are interested in the difference between high and low altitude tennis. I'll break it down into 3 main categories: pace, bounce and strategy. I hope this helps you understand the difference!
Pace of the Ball
With less air resistance at an altitude like Denver, you would expect the ball to travel at greater velocities compared to sea level. You would be correct. The speed of the ball is, in my opinion, the hardest thing to get used to here in Colorado. In fact when players here are training for playing a big tournament at sea level, they often use green-dot balls (used for kids ages 11-12) that give a more accurate bounce and speed to what it will be like when they play at sea level.
Bounce of the Ball
My height definitely helps with this but it is still difficult to handle the high bounces here in Colorado. Especially on the backhand where if a ball gets over your shoulders it makes it very difficult to hit. This forces me to move forward or back to hit the ball waist high. I feel that this has improved my ability to anticipate balls and stay on my toes to constantly be moving to keep the ball within my strike zone.
Best Strategy to Play
High level coaches have a hard time getting players at high altitude to be successful at sea level due to the fact that the style of play in a place like Denver is not necessarily a good strategy for sea level. In Denver, you can get away with rolling the ball (aka lots of topspin) because the ball bounces very high and the ball flies through the air quickly so more spin is more accuracy. At sea level, it is necessary to flatten the ball more as you have more air friction to hit through. Hitting through the ball allows you to penetrate the court more and hit balls that are harder for your opponent to handle. Rolling the ball with a lot of spin won't do as much damage and would require a lot of foot speed (aka Nadal) to get to every ball since you cannot dictate points when hitting with looping balls. So training a player to hit through the ball here in Denver is very risky since it requires a tremendous amount of accuracy for it to pay off.
So Which Pro Would Do Well At High Altitude?
In my opinion, it would have to be a player that hits with tremendous spin as the ball will bounce higher than usual and would be necessary for the needed control. This makes Nadal a perfect candidate to dominate at high altitudes. There has been some signs of this in the past as he has dominated the Madrid and Monte Carlo tournaments (both over 2k in elevation) while struggling at the Barcelona tournament which is at sea level. At sea level, his ball can sit up easier for players to attack (a common strategy against Nadal is to hit to his forehand as it has a lot of spin but doesn't penetrate the court as much) but this doesn't happen as much the higher you go as the ball will bounce higher and faster, making it harder to attack. I remember watching Agassi play here in Denver 5 years ago and he struggled keeping the ball in play as he hits a flatter ball. So when you are playing at altitude, remember the key component of winning is....SPIN!
Want to learn about doubles positioning at the net? Check this video out: