A rider once listed the recovery drinks in his cupboard with their carb-to-protein ratios, from SiS at about 1 to 1 up to Tailwind at 4 to 1, then asked which manufacturer had it right. The thread reached 20 replies without answering him. The ratio printed on a recovery drink is a shorthand for the total carbohydrate in the serving, and out of the four situations a rider meets after a ride, it decides the purchase in only two.

Where The 4 To 1 Recovery Ratio Came From

The number comes from a small set of studies in John Ivy’s laboratory. In the 1992 experiment, 9 male cyclists rode for 2 hours to deplete glycogen on three occasions, then received carbohydrate alone, protein alone, or the two together.

The combination raised the rate of glycogen storage above carbohydrate by itself, and a 2002 follow-up reported the same effect on early post-exercise glycogen recovery. That second paper is the one usually cited as the origin of the modern recovery formula.

The commercial phase began immediately afterward. Endurox R4 built a marketing campaign on the finding and sold 4 to 1 to bike shops for 20 years, and riders who have never read a study still know the number because of it.

The ratio also has institutional backing that has never been withdrawn, since the standing position on nutrient timing recommends roughly 3 or 4 parts carbohydrate to 1 part protein for endurance performance and glycogen resynthesis. The studies underneath that recommendation used 2-hour glycogen-depleting rides in a laboratory with a fixed carbohydrate dose, and a rider eating freely after a long weekend ride is not in that experiment.

Carb To Protein Ratios In Popular Recovery Drinks

Placed on a single range, the products a rider is choosing between spread out further than the marketing suggests.

• Maurten Drink Mix 320, 80 g carbohydrate and 0 g protein.

  A during-exercise fuel and the carbohydrate-only end of the range.

• Skratch Labs Recovery Sport Drink Mix, 35 g carbohydrate and 8 g protein, about 4.4 to 1.
• Tailwind Rebuild Recovery, the older formulation still on shelves, 43 g carbohydrate and 10 g protein, about 4.3 to 1.
• Klean Recovery, 40 g carbohydrate and 10 g protein, 4 to 1.
• Low-fat chocolate milk, 8 fluid ounces, about 26 g carbohydrate and 8 g protein, roughly 3.25 to 1.
• Hammer Recoverite 2.0, 32 g carbohydrate and 10 g protein, about 3.2 to 1.
• First Endurance Ultragen, 60 g carbohydrate and 20 g protein, 3 to 1.
• Tailwind Recovery Mix, the 2025 reformulation, 34 g carbohydrate and 20 g protein, about 1.7 to 1.
• GU Roctane Protein Recovery, 30 g carbohydrate and 20 g whey protein, 1.5 to 1.
• SiS REGO Rapid Recovery, 23 g carbohydrate and 20 g protein, about 1.15 to 1.

Two of those entries come with a warning for anyone shopping from memory. Tailwind moved a mainstream 4 to 1 product to roughly 1.7 to 1 by doubling the protein, and Hammer’s current Recoverite serving is about half the size of the version many riders remember at the same ratio, with retail catalogs listing old and new formulations side by side.

Taste sorts the same products into a third order. Riders who have worked through several of them describe Skratch as the best tasting and the smallest package for the money, and Ultragen as having a metallic edge that some people mix out with almond milk instead of water.

Why Total Carbohydrate Matters More Than The Ratio

Sorting the same 10 products by absolute carbohydrate per serving produces an order that barely resembles the first one. It runs Maurten, Ultragen, Tailwind Rebuild, Klean, Skratch, Tailwind Recovery Mix, Recoverite, GU Roctane, chocolate milk, REGO.

Skratch, marketed at 4.4 to 1, has 35 g of carbohydrate, well under two-thirds of the 60 g in Ultragen at 3 to 1. A rider shopping by the number on the front would take the first of those two and get less of the thing that does the work.

The second ordering is the one the evidence supports. A 2018 review of post-exercise carbohydrate and protein co-ingestion concluded that carbohydrate intake during limited recovery primarily determines muscle glycogen resynthesis and repeated exercise capacity, with 1.2 g per kilogram of body mass per hour maximizing repletion, and that protein co-ingestion helped mainly where carbohydrate intake was sub-optimal at around 0.8 g per kilogram per hour or below. One trial gave riders 1.2 g per kilogram per hour with and without 0.4 g of protein and found no additional glycogen across 3 hours of recovery.

Protein dose follows a different rule, depending on how much muscle a rider has, with a practical range of roughly 20 to 30 g per feeding after a 90-minute session and after a 5-hour one alike.

Carbohydrate is the variable that changes with the ride. A 70 kg rider taking 1.0 to 1.2 g per kilogram in the first hour needs 70 to 84 g of carbohydrate against 20 to 30 g of protein. The result falls between 2.3 to 1 and 4 to 1 before any label is consulted.

Which Recovery Drink To Use In Four Situations

Four situations cover most riders, and in two of them the ratio decides nothing. After an easy 90-minute endurance ride, glycogen was never deeply emptied and a normal next meal restores it inside the day, so any point on the range will do.

A rider eating in a deficit should do the arithmetic before buying at the high-carbohydrate end, since 40 g of carbohydrate is 160 calories of sugar before the protein is counted. One 90 kg rider found he would need roughly 100 g of honey in the drink he mixed himself to reach the target he had been given, while trying to lose 5 kg at the same time. In the remaining two situations the choice changes the outcome.

Two Sessions in One Day

With another hard effort inside 8 hours, carbohydrate needs to start arriving at 1.0 to 1.2 g per kilogram per hour from the moment the ride stops, and this is the one point in post-ride recovery nutrition where the timing is urgent. At that dose the label’s ratio stops carrying information and the carbohydrate figure is the only line to read.

Ultragen gets a 70 kg rider close to target in one serving, at 60 g, and triathletes describe keeping it for weekends with a long ride and a long run instead of using it daily, crediting it with how the next morning goes. Its ratio is 3 to 1, lower than the products marketed for exactly this job.

An Evening Ride With Bed in Two Hours

The high-protein end of the range is supported here by overnight protein synthesis instead of by glycogen. Casein at 40 g, taken about 30 minutes before sleep, raised overnight muscle protein synthesis by roughly 22% and improved whole-body protein balance after evening exercise. A 2023 randomized trial in riders who trained in the evening and took 45 g of casein before bed found higher mitochondrial protein synthesis rates overnight, and mitochondrial adaptation is the endurance-relevant one.

This is also the shake mixed at the kitchen sink with the bike already put away, hours after dinner, so the carbohydrate has arrived from food and only the protein is still owed.

Retailers For Recovery Drinks Across The Ratio Range

A store that stocks only the 3 to 1 end is no use in a week that calls for 1.15 to 1, so range across the ratios is the first thing to look for. Single servings matter almost as much, because a rider needs to try two or three before committing to a tub. A counter with a person behind it then settles the question the label cannot, which is what a rider can drink daily without abandoning the tub. The Feed leads on range and on singles, and the four stores after it each go further on one of these than the others do.

Products at The Feed are filed by brand and by category, never by what is in the scoop, and the macro arithmetic in the list above still falls to the rider. Everything on that list is in one cart, though.

Skratch Recovery, Tailwind Recovery Mix, GU Roctane Protein Recovery, SiS REGO, First Endurance Ultragen, Hammer Recoverite and Maurten Drink Mix all check out together, from the retailer supertri names its official performance nutrition partner for the North American series. Its build-your-own box then sells single servings of drink mixes, so three products can be run through three real training days without owning three tubs.

Excel Sports is a Boulder bike shop with an online storefront, and it carries Skratch Sport Recovery in both the 12-serving and 24-serving sizes alongside Hammer Recoverite 2.0 and SiS REGO Rapid Recovery. That combination puts 4.4 to 1 and 1.15 to 1 on one order form, uncommon among cycling-first retailers, whose recovery shelves skew high-carbohydrate. A shop in the town where Skratch is made, stocking the most protein-heavy product on the market beside it, is a useful sign of what its customers ask for.

BikeTiresDirect goes furthest on the single-serving test.

The Portland retailer, which grew out of a bike club selling imported tires and whose parent company sold to Backcountry in 2025, carries Hammer Recoverite 2.0 as both a 32-serving tub and a box of 12 single serves, alongside First Endurance Ultragen and Tailwind Rebuild singles. A rider can run a mid-range product through two weeks of hard weekends and then buy the tub, or find out in week one that the flavor is unbearable and have spent very little.

TriSports has been triathlon-specific since 1999, merged with Athletes Lounge after Velotech acquired TriSports in 2017, and stocks Hammer Recoverite 2.0 in the 32-serving size for athletes who train twice in a day. Below 3 to 1 the shelf thins out, and a rider after the protein-heavy end shops elsewhere. The depth on the high-carbohydrate end is the point, because a store whose customers race long course keeps those products in stock through the season instead of treating them as a slow-moving line.

All3Sports covers an Atlanta triathlon shop and an online storefront, with First Endurance Ultragen on the shelf and staff who ride and race.

Tolerance is what this store answers better than the others. A drink that causes bloating gets abandoned whatever its label says, and every gram left in the tub after that is wasted money. Asking a person who has sold the same product to local athletes all season is faster than working it out from a product page, and it is the one part of this purchase a catalog cannot help with.

Is Chocolate Milk A Good Recovery Drink

Chocolate milk is roughly 3.25 to 1 without anyone formulating it to that number, which is the strongest evidence the ratio describes a serving instead of specifying one. Three results point three ways.

A 2006 study of 9 trained cyclists tested chocolate milk as a post-exercise recovery aid and found longer time to exhaustion than after a carbohydrate replacement drink. Pooling 12 controlled trials in 2018 produced no effect on time to exhaustion, perceived exertion, heart rate or lactate, on evidence too thin to support a conclusion. A 2025 systematic review then reported reduced serum lactate against other recovery drinks.

One rider dropped recovery mixes for 10 weeks of a high-volume base period, switched to 1% chocolate milk out of curiosity, and could not detect a difference in how he recovered. That result is the ordinary one, and it is why the ratio argument survives without ever being settled.