How To Replenish Electrolytes

Why Do We Need Electrolytes?

Best sodium tab

Have you ever worn a dark colored hat enough that it collects a white line along the bottom edge or brim?

This is physical representation of why endurance athletes need electrolytes – they’re lost in sweat, and if I know anything about endurance sports, I know that they are a sweaty endeavor!

Those white stains that show up when sweaty clothes dry are salt stains, and they can become much more serious than just a cosmetic faux pas.

Some people are saltier sweaters than others, but at some race distance, replacing electrolytes – particularly sodium – becomes an essential part of any race fueling strategy.

This is because excessive sodium loss will induce hyponatremia, which translates to low (hypo) blood (emia) sodium (Na).

Hyponatremia can be caused by excessive sodium loss or plain water consumption.

Sweating a lot and only drinking plain water is a double-edged sword that significantly increases risk of hyponatremia.

Symptoms of hyponatremia include:

  • muscle weakness
  • spasms and cramps
  • extreme fatigue
  • confusion
  • nausea
  • seizures
  • coma
  • and in serious cases, hyponatremia can even be fatal.

Brace yourself for a frightening statistic; 30% of runners finish ultramarathons in a hyponatremic state.

Those with hyponatremia also have ~50% more muscle damage and 30 minute slower completion times than runners adequately replacing sodium during a 161 km race.

Electrolyte supplements and drinks or foods containing a good amount of sodium are required to prevent hyponatremia during long endurance events.

Beverages containing sodium are often the best choice, as they help replace sodium and fluids simultaneously.

How To Replenish Electrolytes The Right Way

This is a particularly tough question to answer as it depends so much on factors that vary from person to person.

Some people are very salty sweaters, while others are not at all.

To put how dramatic this difference is in context, athletes can require anywhere from 100 to 2,500 milligrams of sodium per hour!

An athlete’s sodium needs depend on:

  • How much sodium the athlete’s body is putting into sweat
    • Average: 500 mg per pound of sweat
    • Range: 200 - 1100 mg per pound of sweat
  • Sweat rate
    • Average: 1 Liter per hour
    • Range: 0.5 – 1.75 L per hour
  • Environment
    • Heat will increase sweat rate
    • Humidity will increase sweat rate
    • Acclimatization to race environment helps the body prepare for the event and can alter sodium loss rates

The best way to figure out how best to replace sodium on your own is achieved with a personalized hydration plan.

Determining How Many Electrolytes You Need Using Sweat Rate

how much to drink for a race

Unless you are sure you’re a salty sweater, assume that you are losing about the average amount of sodium per pound of sweat.

Calculate your sweat rate by taking a baseline bodyweight before you go out for a 1 hour run, ride, or swim at race pace. When you’re done, dry off, and weigh yourself again. The amount of weight lost during your workout is equal to the amount of fluid you’ve lost as sweat in one hour.

For example, if you’ve lost 3 pounds during that time, your sweat rate is 3 pounds (1.4 kg or 1.4 liters) per hour.

Now factor in the amount of sodium per pound of sweat. If it is 500 mg per pound than hourly sodium loss is equal to 1,500 mg.

For your race, you will take your hourly sweat and sodium loss rate and break it up into manageable quantities within a 15 minute time frame based on your MIN and MAX fluid needs.

Using the same example as above for an athlete with 60kg bodyweight, average sodium per pound of sweat, and an estimated 3 hour marathon time, we make the following calculations:

  • MAX fluid needs are sweat rate times duration divided by number of 15-minute segments in the total duration of the race.
    • 4 L per hour * 3 hours / 12 = 0.35 L per 15 minutes
  • MIN fluid needs are to prevent loss of no more than 2% bodyweight (when performance becomes compromised) and are related to the MAX need.
    • 60 kg * 0.02 = 1.2 kg or 1.2 L
    • 4 * 3 – 1.2 = 3 L
    • 3 L / 12 = 0.25 L per 15 minutes
  • To replace the necessary sodium add 500mg of sodium to each pound of fluid.
    • 1 pound of fluid = 2.2 L
    • 500 mg of sodium in every 2.2 L of fluid
    • 227 mg of sodium per L of fluid

Therefore, in this example, fluid needs are 0.25 – 0.35 L per 15 minutes, and each liter should contain 227 mg of sodium. Modify the example according to your personal needs.

Besides Sodium, What Are The Other Electrolytes?

best salt for running

Although sodium is the primary electrolyte lost in sweat, other electrolyte minerals are lost as well.

These other electrolytes are:

  • Chloride
  • Potassium
  • Magnesium
  • Calcium

Complications are not as serious as death, but a total electrolyte replacement strategy will contain the other minerals.

For every 100 mg of sodium in sweat, there is also:

  • 78 mg chloride
  • 22 mg potassium
  • 2 mg magnesium
  • 2 mg calcium.

Many of these, and other, minerals are lost during intense exercise at increased rates as well.

Iron, for example, already tends to be low in endurance athletes, particularly runners (over 50% are deficient).

During an hour of running, iron loss may be increased 4-fold normal rates. Thus, just one hour of running increases iron needs by at least 10% per day.

Compounded over time and with a healthy diet low in iron-packed red meat and high in vegetables that reduce iron absorption yields the iron deficiency problem often observed with runners.

This is pretty important, as low iron status significantly reduces endurance exercise performance.

But a word of caution, toxic effects of iron begin at a dose of 10 mg iron per kg bodyweight, so don’t go overboard!

Likewise, magnesium needs are 10-20% greater, potassium (often already under-consumed – we need 4.7 grams per day!) needs another ~200 mg per hour, and calcium an additional ~100mg per day due to systemic loss as a result of exercise – not just the minerals lost in sweat.

Endurance exercise is a demanding task, and the body minerals take a hit!

What to Look For And How To Get Electrolytes From A Supplement

why runners need sodium

  1. Whether drink, tab, or powder, you want to make sure your electrolyte supplement at least has a good deal of sodium - at least 250mg per serving for average sweaters.
  2. Next, make sure the supplement doesn’t have any weird stuff that can cause GI issues. All-too-common ingredients include the sugar alcohols, usually sorbitol but also mannitol and maltitol.
  3. Third, look for a profile of other electrolytes including at least potassium, calcium, and magnesium.
  4. Fourth, over half of you reading this article are in need of some iron, an electrolyte supplement is a prime opportunity.
  5. Finally, having an easily manipulable supplement is best for accurately dialing in your needs – look for a powder or smaller tab to appropriately dose your electrolytes!

ElectroElite is the Best Electrolyte Supplement

electrolyte supplement comparison

For every product EndurElite makes, we do a competitor analysis to see where we can make meaningful improvements for endurance athletes.

Of all the other electrolyte tablets on the market, only 3 meet the criteria of the two most important factors for electrolyte supplements – having enough sodium and not containing ingredients with a tendency to upset the stomach.

What’s worse is 2 don’t even contain much sodium, which honestly is a little scary considering that sodium is cheaper than dirt and that’s the #1 reason an electrolyte supplement should exist in the first place.

Anyhow… ElectroElite contains over 300mg of sodium per serving.

Dextrose, the naturally-occurring form of glucose, is the carbohydrate source used to help hold the tablet together – no sugar alcohols or other gut irritants.

Great, we’ve checked the two major boxes along with 3 other electrolyte supplements.

In common with 2 out of 3, ElectroElite also contains a full profile of other electrolyte minerals, potassium, calcium, and magnesium.

Now, here’s what makes ElectroElite unique!

By providing 2 smaller tablets instead of 1 large tablet, the athlete has greater control over their dosing. Thus, endurance athletes can be even more precise at obtaining their electrolyte needs.

Everything you need, nothing you don’t.

If you’re thinking, “well I’ll just take extra to be safe,” think again. Going a little over may not be a problem, but if by mistake you double up when your initial estimation was adequate, this can lead to unnecessary complications such as GI distress and side stitches.

Finally, and we think this has the potential to be a HUGE deal, ElectroElite is the FIRST to contain iron.

Why has nobody done this before? We don’t know – we think it’s an obviously perfect opportunity to make sure endurance athletes are meeting their iron needs.

Oh, and did we mention, we are also the FIRST to use Himalayan pink salt as a major source of sodium, which in addition to being a natural source of sodium, contains small quantities of other minerals like zinc and iodine to support a healthy metabolism?

Better ingredients. Better athletes!

A New Chapter in Electrolyte Supplementation

Winning with Electrolytes

You’ve heard it and seen it here first.

Soon, you will see the copycat market filled with iron-fortified electrolyte supplements and natural salts.

Keep in mind that EndurElite was honest with you from the jump while others have tried to keep you in the dark.

With ElectroElite, you get everything you need to keep the body functioning strong from the start of the race all the way to the finish:

  • Optimal sodium
  • A full profile of other minerals
  • And economy-supporting iron with a nice, light flavor is perfect for endurance athletes.
Drop a few ElectroElite tabs in your bottle, and race assured knowing that EndurElite has you covered with the best supplements for endurance athletes this side of the Milky Way.


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