Why Every Competitive Swimmer Should Carry a Multifunction Pen

If you grew up in the 2000s, you probably remember those chunky multi-color pens that every kid had in their pencil case. Eight or ten colors in one barrel, perfect for doodling and color-coded notes. But back then, they were a pain—the ink ran out fast, and teachers didn’t let you use them for exams anyway. Fast forward to adult life, and that same pen becomes a different kind of useful. Especially if you’re a competitive swimmer.

Think about it: you’re at the pool at 5:30 a.m., you’ve got a meet sheet to fill out, a training log to update, and maybe a quick note for your coach. You don’t want to carry a whole pencil case in your swim bag. One multi-pen covers checking off sets, marking times, and jotting down drills—all without adding bulk. That’s why I’ve made the switch, and why I think every swimmer should too.

The Real Problem with Most Pens for Swimmers

Let’s be honest: a standard ballpoint is fine for signing a receipt, but it’s useless when you’re trying to write on a damp heat sheet or a laminated card that’s been splashed. Swimmers need a pen that writes on wet-ish paper, dries fast, and doesn’t smudge when you grab it with damp hands. Multi-pens, especially those with oil-based or gel hybrid inks, are often better at this than your average office pen.

But there’s another issue: color. When you’re tracking intervals, you want to see at a glance which set was a sprint and which was recovery. A red or blue ink isn’t just for fun—it’s a functional tool. A multi-pen lets you switch from black to red to blue in a second, no digging around for another pen.

What to Look for in a Multi-Pen

Not all multi-pens are created equal. The key is the refill system. You want something that’s easy to find replacements for, and that doesn’t cost an arm and a leg every time you run out. For swimmers who write a lot—like logging yardage every day—a pen with cheap, widely available refills is a must.

There are two main refill standards: the ISO D1 (2.3mm diameter, 67mm long) and the Japanese standard (3mm diameter, often 88mm or 98mm). The D1 is common in European pens like LAMY, while the Japanese standard is used by Pilot, Pentel, and uni. The good news is that many cheap Chinese multi-pens use the same 3mm refills, so you can often find generic replacements for pennies.

Top Picks for Swimmers

Pilot Coleto: The Customizable Workhorse

If you want a pen that you can make your own, the Pilot Coleto is a great choice. It comes in 2- to 5-barrel versions, and the refills come with their own color-coded buttons—you just pop the top and swap them out. The refill selection is huge: 0.3mm, 0.4mm, and 0.5mm in 33 colors, plus mechanical pencil and eraser modules. That’s perfect for color-coding your swim sets: use blue for warm-up, red for main sets, green for cool-down. The only downside is that the refills are a bit pricey, but they last longer than you’d think if you’re not writing novels.

Pentel i+ and Energel: Fast-Drying Ink

Pentel’s Energel is famous for its quick-drying gel ink, which is a huge plus when you’re writing right after a set and your hands are still a little damp. The i+ system lets you mix and match Energel and Sliccies refills (Sliccies has 15 colors). The pen body is modular, and the refill’s color is visible through a clear window. It’s a solid choice if you want a pen that writes smoothly and doesn’t smudge.

uni Jetstream: The Smooth Operator

uni’s Jetstream is a hybrid oil-based ink that writes like a gel but dries faster. It’s my go-to for meet sheets because it rarely smears, even if you have to close the book quickly. The Jetstream multi-pen is available in many styles, and the refills (8.8cm) are cheap and easy to find. Plus, the ink is consistent and nice to control—good for when you’re scribbling in a hurry between events.

Refill Cost: The Hidden Trap

Here’s the thing: multi-pens are convenient, but the refills can be a money sink. If you’re writing a lot of black or blue, you’ll go through refills faster than you expect. For example, a typical Coleto refill holds about 0.4ml of ink—that’s not a lot. If you’re logging 5,000 yards a day and writing notes, you might burn through a refill in a week.

To save money, look for compatible refills. For the 3mm standard, you can find generic refills at craft stores or online. Just make sure they’re the right length and diameter. For the D1 standard, there are also cheaper alternatives, but they’re less common.

How to Use a Multi-Pen for Swim Training

Here’s a practical tip: keep a multi-pen in your swim bag with a small notepad or a laminated training log. Use blue for your main sets, red for sprints, and green for technique work. That way, when you review your week, you can see at a glance where your effort went. Some swimmers use a pencil module for marking distances on a whiteboard—just make sure the eraser module is handy.

Another idea: use a multi-pen for meet day. You’ll need to write down your events, splits, and times. A pen with a mechanical pencil module is great for making changes without scratching out. And if you’re a coach, a multi-pen is a lifesaver for writing on heat sheets and giving feedback on the deck.

Final Thoughts

I know it sounds silly to spend time thinking about pens when you’re training for a race, but the right tool can make your life easier. A good multi-pen is compact, versatile, and—if you pick the right one—affordable to maintain. Whether you’re a casual lap swimmer or a serious competitor, having a reliable pen that switches colors instantly is a small win that adds up over the season.

So next time you’re at the pool, take a look at your bag. Is there a better pen out there? Probably. But the multi-pen is the one that’ll stick with you through every practice and meet.