Most runners know they need electrolytes as part of their hydration plan. However, not all runners like the typical sports drinks to get their electrolytes. Salt tablets for runners are an alternative to sports drinks. Salt tablets may also be helpful for runners who cramp, even though sodium levels are not the sole cause of muscle cramping. This article delves into how and when to use salt tablets for running.
Do I Need to Take Salt Tablets?
There are two scenarios where sodium tablets are very beneficial for runners: salty sweaters and plain water drinkers.
Serum sodium loss rates vary significantly amongst runners, with heavy salt sweaters losing ~1600 mg per liter of sweat. For those runners, traditional sports drinks may not provide enough sodium to replace their losses. Salt tablets can provide additional sodium with the sports drink. If you are a salty sweater, start small when introducing sodium supplements in addition to a sports drink. (There are some sports drink with higher sodium levels. Before supplementing with salt tablets, always check the sodium levels in your sports drink.)
Some runners prefer the taste of plain water to sports drinks. However, plain water does not provide electrolytes. In order to get electrolytes, these runners need to rely on other sports nutrition products. Electrolyte capsules provide the sodium and other electrolytes you would normally get in a sports drink. (Read more here on why you want electrolytes as part of your hydration plan.)
If you are not an excessively salty sweater, do not experience cramping (see below), and use a sports drink that works well for you, you likely do not need salt tablets. However, if you are doing an ultra-marathon or multi-stage race, it may be useful to bring salt tablets in case you run out of sports drink.
Not all runners will respond positively to salt tablets. For some runners, salt tablets may alter blood pressure and make them feel “off.” Others may notice that they feel overly thirsty from salt tablets. (This is a logical consequence, as sodium stimulates the thirst mechanism).
Will Salt Tablets Stop Muscle Cramps?
Cramping is multifactorial and difficult to measure in scientific studies. When you conduct a scientific study, you need to control as much as you can to understand the relationship between the intervention (salt tablet) and outcome (cramping). While that seems simple, many confounding variables can occur. Serum sodium loss rates will vary tremendously based on individual sweat rates and ambient temperature. Cramping may be caused by multiple mechanisms, with sodium as one of many tipping points. Some runners are more prone to cramping. All in all, cramping becomes difficult to study.
We do know that cramping is not exclusively caused by serum sodium levels. A 2019 review in Sports Medicine defined exercise-induced muscle cramping as a multifactorial phenomenon. The causes may involve altered neuromuscular activity along the spinal reflexes, hydration/sodium balance, and others.
However, so many runners report that the usage of salt tablets reduces cramping during long-distance races (often ultra-marathons or Ironmans). For those athletes, low serum sodium may be the tipping point that allows the perfect storm of neuromuscular excitability and dehydration to cause muscle cramps.
With any supplement, you want to weigh the risk and rewards. Salt tablets are not guaranteed to stop muscle cramps. However, they are also a relatively low-risk supplement (assuming you purchase them from a reputable brand and follow usage instructions). If you chronically suffer from muscle cramps, it may be worth trying salt tablets.
How to Use Salt Tablets for Running
When taking salt tablets, avoid excessive intake. Follow the instructions and do not take them more often than recommended. (An exception is if a registered dietitian individually recommends otherwise.) You may need to experiment to see how often you need salt tablets within the recommended range. Your usage of salt tablets will likely vary based on weather and duration of your run.
One concern with sodium supplementation is hypernatremia (high serum sodium levels). A 2021 observational study in the Clinical Journal of Sport Medicine demonstrated no direct causation of sodium supplementation to hypernatremia. Rather, dehydration and hot weather are triggers for high sodium levels. While hypernatremia is rare, monitor for symptoms such as muscle weakness, fatigue, confusion, and seizures (similar to the symptoms of hyponatremia.)
The Best Salt Tablets for Runners
As with any supplement, salt tablets should be purchased from reputable manufacturers to ensure quality and purity. The salt tablets for runners that I recommend as a sports nutritionist are:
- Salt Stick Fast Chews
- Salt Stick Capsules
- GU Roctane Electrolyte Capsules
- Precision Hydration Electrolyte/Salt Capsules
Disclaimer: I have a MS in Applied Exercise Science with a Sport Nutrition concentration. However, the above is not medical advice. If you have special concerns such as hypertension or certain medications that alter sodium levels, consult a registered dietitian or a medical professional.