As most experienced athletes/bodybuilders/gym-goers will tell you, making progress in the gym becomes harder and harder the more you advance in your training. It’s not uncommon for people who just started working out to experience rapid strength/muscle gains for the first year or two, but then suddenly stop making progress at any kind of considerable rate. It can be frustrating to go to the gym day after day, week after week, and be stuck on the same weight.
Fortunately, there are some supplements out there that can increase your muscular endurance and help you break through your current rep range. But first, let’s tackle a major source of confusion…
Strength Vs. Muscular Endurance
There seems to be a lot of confusion out there regarding the difference between strength and muscular endurance. This is mostly due to supplement companies not properly explaining the ingredients in their products and the fact that in the average person’s mind, they’re the same thing.
While muscular endurance could be viewed as a form of strength, the terms mean different things. Strength is easily measured by the maximum amount of weight you can do on a given exercise (1 Rep Max) whereas muscular endurance can be measured by the amount of reps you can achieve at a given weight that is significantly less than your 1 Rep Max.
Both measures are worth increasing, but the supplements discussed below will not reliably enhance strength. When it comes to increasing muscular endurance, however, they are all quite effective.
Let’s dive right in…
Beta-Alanine is a precursor to the dipeptide (combination of two amino acids) Carnosine, higher muscular concentrations of which are associated with greater muscular endurance. Study after study after study has shown that athletes with higher muscle Carnosine levels show consistently greater muscular endurance.
Carnosine helps to reduce Lactic Acid build-up in working muscle tissue which typically results in more prolonged performance at a given work load. Anyone who works out or plays a spot can benefit from Beta-Alanine supplementation. It works in men, women, beginners, experts, etc.
Although Beta-Alanine is just one of the two amino acids involved in Carnosine synthesis—the other being Histidine—it is the rate limiting factor. This means that Beta-Alanine alone is sufficient for increasing muscular Carnosine concentrations.
Some companies toss Histidine in to the mix just because but this is unnecessary and definitely not worth paying an extra premium for. Beta-Alanine is all you need!
Research has consistently demonstrated that 3-6g of Beta-Alanine per day can increase Carnosine levels and improve endurance in as two weeks. Lower doses, such as 1.6g/day will still increase Carnosine in the long run, but will take longer to do so than higher doses.
Many users of Beta-Alanine report a tingling sensation shortly after consumption. To be clear, this is a harmless side effect—called Parasthesia—which indicates nothing about whether it’s working or not.
Many companies under-dose Beta-Alanine and rely on the perception that “the tingling sensation means it’s working”, but this isn’t true. In order to maximize the benefits of Beta-Alanine, you should consume 3-6g daily.
Citrulline is a precursor to the amino acid Arginine and therefore plays a vital role in Nitric Oxide production. While it is true that Citrulline is a Nitric Oxide booster that works much better than Arginine (on a gram for gram basis), it also has an additional mechanism by which it enhances exercise performance.
Citrulline is one of the three amino acids involved in the Urea Cycle, a detoxification process by which harmful substances like Ammonia are converted to the harmless substance Urea and released from the body.
Ammonia, like Lactic Acid, builds up in muscle tissue during exercise and contributes to muscular fatigue. Citrulline is capable of reducing Ammonia build-up in working muscle tissue, thereby delaying fatigue.
In studies, this reduced Ammonia build-up manifests itself in the form of more reps at a given percentage (say 80%) of 1 Rep Max. In other words, Citrulline does not increase the total amount of weight you can do (1 Rep Max), but will allow you to squeeze out a few extra reps at a lower weight.
While Citrulline may potentially influence Nitric Oxide production at lower doses (1-2g), most studies investigating performance enhancement have used 6-9g, usually as Citrulline Malate.
Citrulline Malate is simply L-Citrulline bonded with Malic Acid and while both L-Citrulline and Citrulline Malate may be effective, Citrulline Malate is the preferred form to use if you want to enhance your muscular endurance. Try supplementing with 6g just prior to your workout.
Caffeine is a stimulant, unlike the other supplements discussed above, capable of increasing focus and perceived energy which ultimately leads to better workouts in most people. Although there is some evidence to suggest that Caffeine can increase power output, it is more reliable at increasing muscular endurance.
Several theories have been suggested to explain why Caffeine increases muscular endurance, but the leading theory is simply that it reduces the perception of pain and fatigue. It is true that Caffeine increases fat-oxidation as well, but this likely doesn’t influence performance directly.
Unlike the other supplements we discussed above, Caffeine requires some trial and error to find your ideal dose. This is simply because tolerance varies considerably from person to person. Some people can feel the effects with as little as 50-100mg while others require much higher doses like 300-400mg.
Most people will find their sweet spot somewhere between 200-300mg.
The Bottom Line On Muscular Endurance
If your goal is to build muscle, you should ideally be looking for ways to enhance muscular endurance during your training sessions. Better muscular endurance during your workouts will lead to more intense workouts which will translate into greater gains.