- By Jeff Rothschild 

Sports supplements are everywhere. Most don’t live up to their claims, but there are a few that actually do! When it comes to enhancing endurance performance, some of the most well-studied are sodium bicarbonate, beta-alanine, beetroot juice, and caffeine, each of which can typically offer ~1-3% improvements across a variety of endurance-related measures. Unfortunately, they typically don’t synergize and offer compounding benefits, but they can all help in different ways and at different times.

If supplements are good for helping you go faster on race day, what happens if you take them all the time? 

Do they wear off and lose their effect? Can they continue to offer the same benefit? Can they actually help your training? I recently published a review paper on this topic (1) and wanted to share some of the key takeaways.After reviewing 100+ papers testing the effects of supplements on endurance training adaptations, it looks like you may indeed be able to gain additional benefits from training by synergizing certain supplements with your workouts. The most likely way this happens is by allowing you to train harder, which doesn’t necessarily mean more hours but rather during interval workouts, for example, you may be able to accumulate more “work” during each session. If two groups of athletes are participating in a training protocol (one taking a supplement and one taking a placebo), and the training intensity is matched based on wattage, heart rate, etc., then most supplements typically won’t offer any additional benefit (although there are some exceptions to this). If the intervals are allowed to be “unclamped” (e.g. 4 min intervals at maximal effort) and the supplement allows the athlete to produce a greater power output throughout the session, then a greater “adaptation signal” can be produced. Because training, at its core, is the accumulation of these “adaptation signals” (i.e. molecular responses) over time, more “signal” following each workout can mean more “adaptations” over time.

Do the effects of a supplement “wear off”?

Not likely. While you may not notice the effects of a supplement you use every day as much because you’ll be more “used to” going faster, these supplements don’t appear to lose their ergogenic (performance-enhancing) effects over time.Many people think that habitual caffeine usage will decrease its efficacy, but research has shown  improved cycling time-trial performance in people who are habitually low-, moderate-, and high-caffeine consumers [2, 3], and the ingestion of 3 mg/kg of caffeine for 20 days in a row continued to produce beneficial effects [4]. This supports the idea that regular caffeine consumption during training sessions should not reduce its longer-term impact, however very little research actually exists in this area. 

What about antioxidants? 

This is an interesting and somewhat controversial area. Taking high-dose antioxidant supplements like vitamin C or E appears to block some of the adaptive responses to training, however no studies have shown any performance declines from taking them. Other antioxidants (green tea extract, resveratrol, etc.) have a lot of nuance to their effects and more research is needed before we can make strong recommendations. 

Okay, how do I know which is right for me and how do I do it? 

It’s always smart to talk with a qualified sports dietitian/nutritionist. In addition, here are a few noteworthy things to consider. 

Sodium bicarbonate – For starters, baking soda tastes terrible! But if you can get past that and figure out the right dose for you (too much can make you run to the bathroom), it can take your training and racing up to a new level. By acting as a buffering agent, it can prevent/reduce the normal drop in pH during high-intensity exercise and allow you to go “harder, longer” during high-intensity exercise. The typical serving is 0.2–0.4 g/kg body weight, usually divided across 1-3 doses, 30-90 mins prior to exercise. The nice thing about this is that it should work immediately – meaning you don’t need to go through any type of loading phase. This could be used before any hard interval session to allow a greater work output, and also before an endurance session to cause a pH shift that has the potential to improve mitochondrial adaptations. 

Beta-alanine – There are several ways in which beta-alanine can offer benefit but is most often thought of as a buffering agent that can also allow you to go “harder, longer” during high-intensity exercise. It does require some commitment to take, because to be effective you need to take ~4-6 g per day, every day, for about 4 weeks. This is usually split across 3-4 servings per day to avoid the (otherwise-harmless) tingling feeling. So, while sodium bicarbonate can work today, you need to be consistent with beta-alanine for several weeks before it starts helping things. Because of this, you don’t have to think about what type of workouts to take it before (endurance vs. interval, etc.) because it will be in your system and you can maintain your normal training (while likely accumulating more work during interval sessions). 

Beetroot juice – This is an increasingly popular supplement, and comes in several forms (drinks, concentrated shots, powders, etc.). While the term “dietary nitrate” is often used interchangeably with beetroot juice, nitrates are just a part of beetroot juice and a number of studies show differential effects from consuming beetroot juice and isolated nitrate (1). Beetroot juice can be effective following a single dose 2-3 hours prior to exercise but seems to work better when taking it for several days in a row. It works via a number of different mechanisms relating to oxygen efficiency and muscle fibre-type remodeling, and has potential to improve adaptations to both high-intensity and endurance-type of training. A word of caution though, the nitrate content of different products can vary drastically (see below). The picture shows what is thought to be the minimal effective dose, and that requirement may even be up to 2x higher for more highly trained athletes. This doesn’t mean it shouldn’t be used, but you may have to take a few servings depending on the brand. 

Figure 1. The nitrate content of different products can vary drastically and many recommended serving sizes contain less nitrate than the minimal effective dose. Gallardo and Coggan 2018 (5)  

 Table 1: Summary of the effects, dosages and benefits of sodium bicarbonate, beta-alanine, beetroot juice and caffeine. 

Summary

The most important factors affecting the adaptations to endurance training are the training stimuli volume and intensity. However, within a given training program, the appropriate use of dietary supplements may offer additional benefits. Of course, for drug-tested athletes in particular, caution should be used when choosing supplements to find products that have been 3^rd-party tested for label accuracy and to be free of banned substances.

If you'd like to learn more about how to optimize your long distance triathlon performance, check out our Endure IQ online courses