Last Updated on January 22, 2022 by Heather Hart, ACSM EP, CSCS
Disclaimer: I dislike 99% of endurance gels on the market. The consistency makes me gag, the taste is unsettling, and they piss off my stomach. So when my friend Brian offered up a Science in Sport / SiS GO isotonic energy gel mid run, I politely took it and tucked it into my hydration pack for “later”.
Later meaning, probably never.
Except a few runs later, I found myself in a precarious situation: I was running, and I was bonking…and I forgot to bring any sort of calories to save me from myself. But the SiS gel was still in my pack. Desperate to remove myself from this horrible, hangry, rungry demise…I took the SiS gel. I braced myself for all of the things I immediately hate: the gag worthy consistency and subpar taste…
And I was immediately pleasantly surprised.
Long story short, my husband and I are now Science in Sport converts, and have an entire closet full of their products (gels, bars, and electrolyte drink tabs) that we bought and paid for ourselves. My reviews are always honest, sponsored or not, but I’m sharing to preface this post with the fact that we not only enjoy their products, we regularly buy them.
What makes SiS GO isotonic energy gels different?
The SiS GO isotonic energy gel is an isotonic gel (the worlds first, according to their website). What does that mean? It’s a chemistry term that essentially means an external solution – in this case, the gel – has the same osmolarity (concentration) as the cell – in this case, your cells -, and there will be no net movement of water into or out of the cell.
“Laymen’s terms, please, Heather…”
In short it means that this gel can not only be digested without water, it’s not going to pull water from your body in order to be utilized. Another perk is that because it was designed to be consumed without water, it minimizes the risk of being bloated that can sometimes occur with over-drinking. (Raise your hand if you’ve ever been in that uncomfortable sloshy bloat belly boat…I know I have.)
Why haven’t I heard of Science in Sport before?
Science in Sport is a United Kingdom based company, and by looking at their social media profiles, seem to cater mostly to road cyclists. BUT, SiS is indeed available in the United States (and we’ve had AMAZING experiences ordering online & with their customer service). And as far as endurance sports nutrition goes: if it works on the bike, it’s going to work on the run or the trail too (assuming you, like me, are a hopeless trail running addict).
SiS gels come in a few different options. The standard, Isotonic Energy gel contains 22 grams of rapidly absorbed carbohydrates per gel (maltodextrin, specifically). Each gel is 90 calories, with less than 1 gram of sugar, and 10 mg of sodium.
There is a GO energy + caffeine option, that contains 75 mg of caffeine, in addition to the same nutritional listings in the standard SiS Go Energy gel.
Lastly, there is a GO energy + electrolyte gel, that contains 118mg sodium, 9.5mg potassium and 1.5mg magnesium per gel, on top of the 22 grams of carbs. It should be noted that the electrolyte version is not isotonic as the additional of electrolytes increases the concentration.
The ingredients of all SiS GO energy gels are vegan, contain natural flavorings, and do not use aspartame.
Okay, but can you REALLY take SiS gels without water?
I’m skeptical of any “you don’t need water” claims, especially because I crave water like a fish stranded on shore. I’ve been known to wear my hydration pack for a 6 miler.
However, I’m happy to report that no, you don’t need water with an SiS gel. The consistency – stay with me now – is much like halfway gelled Jello. I can’t be the only one who didn’t have the patience as a kid to wait for the Jello to completely gel, am I? SiS gels aren’t quite liquid, but they are definitely far from the sticky solid of a standard endurance gel.
If you’re not familiar with Jello, perhaps these comparisons will resonate:
“It’s like warm, high quality, REAL maple syrup. Not the cheap fake stuff.” – Geoff
“It’s like a melted ice pop!” – Brian
I’d also say it’s even more watery than applesauce, but thicker than apple juice. Point being, it’s liquid enough (and the taste more than palatable) to not feel like you need to wash it down with water after ingesting the gel.
SiS GO Isotonic Gel Taste Test:
The taste of SiS GO energy gels is quite enjoyable, definitely a step above “tolerable”. The Orange and Lemon & Lime flavors remind me, again, of Jello. Apple and tropical are tasty, and I admittedly haven’t tried Tutti Fruitti or Cherry yet.
The Berry flavor of Energy + caffeine has a very slight bitter taste to it. It’s nothing distracting, but enough that you can tell that there is indeed caffeine added to the gel. And the caffeine level did not leave me feeling jittery, nor did it cause a caffeine crash. Disclaimer: I love caffeine and consume probably more than I should per day, so my caffeine tolerance is high.
The Salted Watermelon energy + electrolytes has the slightest salty taste. It’s definitely refreshing when you are sweating your tail off and craving a little salt.
The Gut Test:
Most important part of the review: did my gastrointestinal system approve of the SiS GO isotonic energy gels? A resounding YES. I’ve used these in training runs upwards of 25 miles, as well as my last 50 mile race, with zero stomach issues to report. Praise the running Gods, and the crew over at Science in Sport.
Of course, when it comes to training and race day nutrition, everyone’s stomach responds differently . What works for me might not work for you, and what works for you, might not work for me. You get the idea.
Fortunately, Science in Sport makes it super easy to give their SiS GO Isotonic Energy Gels a try, with a 6 gel variety pack that is almost always on sale (currently on sale for $5.72).
In summary: I love this stuff, and I’ll be using it for my training and racing from now on (supplemented with grilled cheese sandwiches at mile 50, obviously). If you are looking for a convenient sports / endurance nutrition energy supplement, but you haven’t had luck with gels so far, I definitely recommend giving Sport in Science a try.
This post sponsored by my husband, who bought all the SiS gels that I stole from his stash in the closet in order to write this post.