Polyester (or co-poly) strings are among the least powerful and uncomfortable tennis strings on the market (Kevlar being the least powerful of all).
So why are people using them?
Control, durability and perceived spin benefits are the main drivers behind the popularity. These strings are ideal for the pros, hard hitting juniors and chronic string breakers.
If you need more power, want more feel, don’t break strings frequently or have ANY issues with your shoulder, elbow or wrist, you are probably wise to stay away from these types of strings.
Here are some string facts that might be of interest if you are currently using polyester or
considering trying it:
Natural Gut is the ultimate in playability, feel, tension maintenance and also by far the most expensive.
Synthetic Gut (aka Nylon) is generally referring to solid core synthetic gut strings which are the most economical way to go as it delivers a good combination of playability and durability.
Multifilament strings offer more comfort and power than solid core synthetic gut strings, but with slightly less durability and tension maintenance. Polyester or Co-polyester has very little power and it is extremely stiff (even the “soft” polys) thus not very arm friendly, but offers great durability and control.
Natural Gut – the ultimate in playability, feel and tension maintenance. Often overlooked due to its cost, natural gut is the best choice for players with arm problems or those who crave its sublime, comfortably crisp feel. Commonly used in hybrids, combining polyester mains with natural gut crosses (with some players using gut in the mains for more power and feel). Natural gut offers maximum feel and control due to its ultra low stiffness, which provides phenomenal ball “pocketing”. Made from individual strands of intestines (usually from cows), this string is also one of the priciest. Used by club players and touring pros alike, natural gut was originally extremely sensitive to water and weather changes, but modern coatings and treatments have decreased this risk greatly. Even so, make sure to keep it out of the rain and the trunk of your car as Florida heat is not kind to tennis strings.
Nylon – Synthetic Gut or Nylon? Most Synthetic Gut string are made with nylon. Commonly referred to Synthetic Gut, these strings deliver a good combination of playability and durability at a great price. Basic Synthetic Gut is typically made with a solid core, and this is the most economical way to go.
Nylon multifilaments offer more comfort and power. Unlike the more basic Synthetic Gut strings, multifilaments are comprised of hundreds or thousands of ultra pliable, elbow-friendly fibers, and bundled together with flexible resins like polyurethane. Multifilament tennis strings have become quite popular over the years and is considered by some to be the top category of string construction after natural gut. Multifilament strings are created through the process similar to natural gut by weaving hundreds or thousands of microfibers together. The result is a string with that provides a soft almost cushion like feel. As a result, these strings have become a great option for players suffering from arm injuries. Some players are surprised or slightly confused by the fraying that occurs with multifilament strings as they wear down, but this is a natural result of the breakage of the tiny fibers used to create these strings.
Multifilaments often tend to be a bit more expensive, but is a cheaper alternative to natural gut. Most multifilaments lose tension faster than a string with a solid center core and durability is slightly less than solid core strings. Pre-stretching the string before stringing helps reduce the tension loss and of course we do this at e-tennis (as we do with all strings).
Polyester- A type of string design where one string material, or a combination of materials, is extruded, or drawn through a geometrically shaped dye, to form a solid piece of string. Monofilament strings tend to exhibit greater durability than synthetic gut or multifilament strings of the same material, but have less power, feel, and comfort. The lower elasticity of these strings requires full, fast swings to maximize their performance. Polyester is the number one choice on the pro tour because it allows advanced ball strikers to maintain surgical control on their fastest, most aggressive strokes because of the string’s lack of power. The incredible stroke speed enabled by polyester also translates into categorically higher level of spin, which literally changes the trajectories and angles available to the player. Unfortunately, most recreational players will rarely be able to generate enough racquet speed to take advantage of this added spin magic.
While it is still extremely stiff and dead for recreational players, a growing number of string manufacturers have devoted the lion’s share of their R&D to creating softer, more elastic polys, but the result is still very stiff strings so be very cautious if you have any arm issues. Another way to get the benefits of polyester is through a hybrid, also very popular on the pro tour. This is typically done by combining polyester (usually in the mains) with natural gut or multifilament crosses. This setup provides the durability, control and spin of polyester with the comfort, power and touch of a softer string – otherwise known as the best of both worlds. Due to its high stiffness and relatively low power, polyester is not recommended for beginners or players with arm injuries.
If players are looking for added durability polyester can be a solid option, and due to the stiffness of the string you will see very little string movement. However, polyester-based strings are known for losing tension fairly quickly.
Kevlar – The most durable string available, but has fallen out of favor as Polyester type strings are exploding in popularity. Kevlar is very stiff and strings up very tight. Ultimately, Kevlar hybrids are the least powerful and least comfortable strings currently available. Not recommended for beginners or players with arm injuries.
• Generate more power
• Generate more spin
• Have less durability
• Have more comfort
• Have more tension loss
• Generate less power
• Generate less spin
• Have more durability
• Have less comfort
• Lower string tensions generate more power
• Higher string tensions generate more ball control
• Rackets with fewer strings (or string density) generate more power
• Rackets with few strings also generate more spin
• Rackets with tight string beds give more control