Athletes tend to carry an impressive amount of tech on their wrists. Too bad what holds it on is often badly designed and poorly manufactured. Even expensive smartwatches can come with straps that unsuited for outdoor sports, especially if you are living the Triathlon Lifestyle ™.
In the case of triathletes, we need our electronics to stay put and take a beating under a wide variety of conditions, including salt water, sand and sun, not to mention rapid changes in transition. This places many demands on the watch strap for comfort, strength and longevity. Relatively few straps meet all these demands.
Let's examine the watch strap in detail, starting where it meets the watch.
Strap Attachment:
The vast majority of straps connect to the watch using a spring-loaded bar that fits through the ends of the strap and into lugs (holes) on the watch body. The "size" of such straps is simply the separation between the lugs, which for most sports watches is either 20mm or 22mm. Some bars have a tiny side knob which makes them easier to manipulate without tools.
Some smartwatches use custom attachment methods. My Fitbit Charge 3 uses an ingenious, simple, secure and reliable latch. Apple and others have similar-but-different attachment methods. However, most watches use the spring-bar and lugs style, which means there are more of that type of strap on the market, so that's what we'll be looking at going forward.
Strap Material:
Next comes the strap itself. There are many strap materials available, including:
- Leather
- Woven nylon
- Fabric
- Silicone and/or TPU
- Metal links or mesh
- Elastic
Which strap material is best for sports use? We want something that will stand up to lots of abuse (sun, water, sand, sweat) yet be both comfortable and durable. If we look at what sport watch manufacturers use, it's pretty much always silicone (better) or TPU (worse).
Why use silicone? It is slightly stretchy yet strong, flexible and comfortable, and extremely durable. While silicone itself is far from the cheapest material in the above list, it's popularity makes it low-cost. Going forward, we'll assume our ideal strap will be made of silicone.
TPU isn't as durable as silicone, it isn't as stretchy, and it can become brittle or change color over time.
Strap Closure:
There are several ways to join the two halves of a watch strap at the back of your wrist:
- Buckle with Tang (tongue)
- Velcro
- Button
- Metal folding hinge
- Latch (mechanical or magnetic)
- Elastic strap (no fastener)
From a sports perspective, we want a closure that is adjustable, secure (stays closed), and doesn't snag. Why adjustable? We may want to wear our watch over clothing, such as a jacket or wetsuit, so adjustability is needed, also to allow for changes in wrist diameter due to muscle use and hydration. Why secure? We are active, and having a watch strap come undone is the easiest way to lose an expensive bit of kit. Why no snag? We move our arms hard and fast, meaning the watch can brush against the sides of our body, impacting skin, clothing or wetsuit: The watch closure shouldn't harm us or our other gear!
Of the above closure types, "buckle and tang" has a metal tongue always exposed, meaning it can easily lead to snags as arms move rapidly. Most metal closures, including latches and hinges, can also cause snags.
Elastic straps can have a problem holding the watch snug and stationary against the wrist to permit an optical sensor (heartrate, oxygenation, etc.) to work properly. And their stretchiness tends to fade quickly with use and exposure to the elements.
Velcro may seem ideal, but it wears out quickly, and can let go without being noticed. (I've lost two swim watches that had Velcro straps.)
That leaves us with the button closure being best for sports use. It can't snag, it is secure, and it is easy to use.
Strap Keeper:
Some closure types (folding hinge, elastic) permit there to be no excess strap. Unfortunately, they either aren't easily adjustable, or are so adjustable they can't do the job. So our strap will have a tail. How best to deal with it?
The vast majority of strap designs have the tail directed to the outside of the strap, to be held in place by one or more small loops called "keepers". If the keepers aren't properly positioned and held in place, the tail will come loose, leading to snags and even to the strap coming undone.
The alternative is to route the tail to the inside of the strap, against the wrist. This has the advantages of needing no separate keepers and being inherently snag-proof. This has the disadvantage that it requires the other half of the strap have a hole in it through which the tail will pass. This hole can weaken the strap, and is easily the greatest cause of failure for poorly made straps of this type.
The Strap System:
Now that we've identified the watch strap components, let's look at how they may best be combined to make a strap that will withstand the abuse an athlete will apply.
One strap requirement not previously mentioned is ventilation: We don't want the strap to trap sweat or sand against our skin. One way to ensure this is to have a loose strap, but that won't work because it will prevent the optical sensors from functioning, not to mention letting the watch get spun to the wrong side of the wrist making it impossible to read.
The strap must be snug, which means any trapped water or sand must be able to pass through the strap itself, meaning the strap material must either have an open weave or be perforated. Since silicone is already our chosen material, this means we want perforated silicone.
But won't punching holes in the strap make it weaker? Sure, but remember the keeper? A perforated strap must use stronger materials, which means the hole needed to route the strap tail through to be against the wrist will also be strong, and be less likely to cause a problem.
Conclusion:
The ideal watch strap for athletes (IMHO) is shown below, and is the kind of strap I've been using for over two years. I recommend getting this kind of strap immediately after getting a new watch. Keep the factory strap as a backup, though you'll likely use that strap only when selling the watch.
This particular style is available for every attachment type and size. To ensure you get a compatible strap, search for your particular watch brand and model. Unfortunately, you may have trouble finding this kind of strap on Amazon: The Amazon search engine seems to actively hide them! Fortunately, this strap and many like it are easy to find on eBay, and at half the Amazon price.
Some details to note:
- The button clasp is machined from stainless steel. Avoid buttons made from other metals or are chrome-plated, as they may wear or corrode over time.
- Two strap materials are used. Both are silicone, though the black is more firm (and may be stronger) than the yellow which is soft and comfortable against the skin.
- The 2 mm holes are placed 5 mm apart. They are large enough to let sand and sweat out, yet are not so large or so close together that they remove too much material from the strap.
- There is no perforation on the ends next to the watch. This part of the strap gets the most stress and needs to be strongest, especially when the watch itself gets snagged on something (such as when taking off a wetsuit).
