- Temperature is dropping
- Takes longer to warm up
- Cold and wet tennis balls
- More layers on you so can be harder to swing
- More prone to injury as muscles aren't as flexible
One thing that can help with all of these factors is a fresh set of strings. All the factors above combine with the result being a decrease in power.
You cannot expect the same result from your racket and strings in the summer as in Winter, so to help your performance level stay the same drop your string tension a few pounds. This drop in tension increases the sweet spot, gives the string-bed a greater trampoline effect resulting in more power and spin potential.
One important factor to note, strings that have lost tension over time are not the same as freshly installed strings at a lower tension. Strings that have lost tension have done so because they have lost their elasticity. When this happens you lose control, your spin potential drops and your risk of injury increases.
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