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Hammer Under 3 Hours and Over 3 Hours

Clearing up the Confusion


The variety of fuels that Hammer offers and how we explain their best use has inadvertently caused much confusion. Hopefully, this article and accompanying video will clarify this for you and everyone else.

Back in 1992, when I introduced Sustained Energy, it was intended for our Clients engaging in long-distance, mega-endurance efforts. In the late 80s and early 90s, ultra, distance events were increasing, and there were no products designed or intended for long periods. The only available fuels were the usual sugar, citric acid, and salt combo, and they did not work for ultra distances.

However, shortly after introducing Sustained Energy, giving athletes a real ultra fuel, I realized there was a lack of carb fuels for higher intensity, shorter duration exercise. It turns out the products of the day were not working for many athletes even in these shorter durations. This led me to develop Hammer Gel and then HEED.

The introduction of Hammer Gel in 1995 and HEED in 2004 created the need to differentiate the products and their best uses. To help facilitate this, we started talking about exercise periods lasting less than or more than three hours so you would know which fuel is best based on the duration of your exercise. The introduction of Perpetuem in 2002 increased this need.

Since then, we've been suggesting that athletes think about fueling for their exercise bouts with a hard dividing line of under three hours or over three hours. If you exercise for 1-3 hours, use Hammer Gel if you are a water drinker, and HEED if you are a drink drinker (see my other article/video on this subject): Both are complex carb-only fuels that provide a quick boost for these durations.

However, if you plan to exercise for longer than 3 hours, Perpetuem or possibly Sustained Energy should be your primary source of calories. They contain protein, and Perpetuem even has some fat in it.

The above instructions confused many clients and even some of our staff. No one is confused about exercise lasting less than 3 hours – use Hammer Gel or HEED, and you'll be golden. It's the 3 + hours fueling where things get confusing. Even today, I regularly hear clients asking:

“Does that mean for my long events, I start with HEED or Gel for the first three hours, THEN switch to Perpetuem or Sustained Energy?”

NOPE. This is absolutely not what I am trying to convey.

The big idea here is that when you exercise for 3 + hours, you forego the Gel/Heed and start immediately with your protein-fortified fuel. This is super key and the big takeaway here.

After many hours, to avoid flavor fatigue, to change things up, or for more energy towards the end.

Sustained Energy and Perpetuem

Either or both, this magical combo is for the long days.
We’re talking about 3, 6, 12, 24, 36 hours, and beyond.
The difference is both Sustained Energy and Perpetuem contain protein. Heed and Gel do not.
This is especially important because, after about 1.5 hours, your body will begin burning some protein in the gluconeogenesis process.
In fact, roughly 10% of calories converted to glycogen will come from protein.
That said, if you're not consuming a steady protein source during these long activities, it has to come from somewhere.
By using a carb-only fuel source, after a while, your body will have to start robbing protein from… you guessed it - your hard-earned muscle mass.
This will cannibalize your precious muscle and accelerate fatigue – both of which we want to avoid.
Sustained Energy and Perpetuem are here to fill the void and help offset what you are burning.
Furthermore, Perpetuem has the Bonus advantage of having some fat to help with fat metabolism. (Read more here on ENW, all about the many benefits of some Good Fat!)

Cheat Sheet

Jot this down…

Under 3 hours: HEED and/or Hammer Gel alone is fine.

3 hours or more: Use Sustained Energy and/or Perpetuem from the start.
Start sipping away 10-15 in and continuously throughout your activity.
After 6-12 hours or more, to break up the flavor fatigue, go ahead and have a little HEED or Gel for a palette perk and to get up that next hill.


Looking for some guidance on my upcoming Kona triathlon. I have been using perpetual and electolite drinks but am concerned about the heat and what to do to make sure that my nutrition is on point
Hammer Nutrition replied:
Hello Colleen, thank you for reaching out, we can definitely help you dial in your plan for Kona. Please start by reading our IM fueling guide and my 5 SOS. Next, we can set up a call for later this week, like Thursday to go over everything and create your plan. I’ll follow up with a separate email. BDF


I’m somewhat a newbee at cycling. That you very much for this information. I will testify that the HEED has tremendously changed my energy from 20 miles to 60 miles almost over night. I tell everyone how great your products work. Thanks again for your help with my retired experience cycling.
Hammer Nutrition replied:
Hello Thomas, thank you for your comments, I’m glad you’ve been enjoying the HEED and your newfound sport. When you decide to do a century, or more, that’s when adding Perpetuem and Endurolytes in one or more forms, will allow you to keep enjoying the ride all the way! Of course, we’ll be here to help you get everything sorted. BDF

Thomas lippert

Does this apply to non-racing where the efforts are much lower though every bit as long? I’m talking about almost all day recovery ride pace.
Hammer Nutrition replied:
Hi Peter, thank you for your question. The short answer is yes, especially if you are doing rides like this with any frequency. Preserving lean muscle mass is always a concern and priority for me. To elaborate; even at lower levels of intensity where the highest percentage of fat utilization will occur, glycogen is being used in the muscles and converted into glycogen in the liver. Protein breakdown through the gluconeogenesis process is also active, so consuming protein is still key. At a lower pace, protein could be consumed from solid foods (bites of protein bar, raw nuts, etc.) as well as something like Perpetuem, Sustained Energy, or BCAA capsules. BDF

Peter van der Hoeven

Brian, thanks for the insight into what I previously thought of as a “grey area” when choosing between HEED or Perpetuem for a workout – this is great information!

On another note – without a doubt, Perpetuem is the best fuel for long distance endurance efforts, period! It was absolutely an integral part of my successful race strategy to finish the 2022 Unbound XL, along with a tremendous amount of invaluable advice from your Fueling Expert Steve Born! For over 33 hours on my bike, Perpetuem kept me fueled and feeling great!

Thank you for providing such a great product and the support to get the most out of it!
Hammer Nutrition replied:
Hello Grainger, Thank you for your comments! I’ve added Steve on this too since he worked so closely with you on your preparation for this event. So glad it went according to plan! Thank you for your support and encouragement, it keeps us going! BDF

Grainger Pierce

Are either of the 3+ hour fuels available in a non liquid form? My stomach tends to object to any liquids that aren’t water, but I can tolerate mild solids and gels.
Hammer Nutrition replied:
Hello Krysten, Thank you for your questions. The short answer is yes. We do make Perpetuem in solid form (Perpetuem SOLIDS), but not Sustained Energy. However, it’s important to differentiate Hammer liquid fuels from all other brands. Most or all other brands feature a lot of sugar, fructose being worst, along with plenty of citric acid for flavor “tartness” – Unfortunately, these are also the ingredients that cause the stomach problems you and most other athletes experience. Neither Perpetuem or Sustained Energy contain any of these ingredients and are usually well tolerated by athletes with the most sensitive stomach, as long as they don’t over consume. BDF

Krysten Boele

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