Bone broth - what’s old is new again for athletes
by Rachel Jesson

FUNCTIONAL SPORTS NUTRITION - July/Aug 2017

Despite being around for centuries, bone broth is a new food trend for athletes. Rachel Jesson explains the benefits of bone broth and why it should be part of every athlete’s nutritional regime.

There seems to be growing interest in ancestral foods, and a move towards the diets and habits that sustained our ancestors, which fortunately shuns processed foods. From this, bone stocks (broth) have been revisited and are gaining momentum in the sports world.

Broths date back to the stone age when people did not have pots to cook bones in. Instead, they used abdominal pouches of slaughtered animals in order to simmer up meat, fat and bone. Until modern day, most households kept a cauldron continuously simmering over a fire, and ingredients would be added when they became available. People regularly ate from it, making long, slow cooked foods the original ‘fast food’. Sally Morell found that; ‘anecdotal reports abound on the power of broth to relieve headaches, calm the mind, chase butterflies from the stomach, improve focus, and gain energy (1).”

A good quality bone broth is made using pasture-reared bones, joints, tendons, ligaments, skin and muscle, purified water and a good quality vinegar. These are normally boiled in a slow cooker for a long period of time. The vinegar and boiling helps to extract the minerals from the bones and break down the cartilaginous bits into absorbable collagen and gelatine. The end result is normally a gelatinous, nutritious and rich stock that can be sipped as is, or added to foods. According to Melissa Hartwig, consuming broth improves digestion, aids muscle repair and growth, reduces joint pain, promotes a balanced nervous system and strengthens the immune system (2).

Broths are now being distributed towards the final aid stations of some Ironman and marathons events across the globe. Salt is lost during prolonged sweating and broths are used to replace this salt and therefore reduce the incidence of muscle cramps and dizziness. According to Lauren Antonucci, sipping broth late in a race could play a role in maintaining the fluid balance, because the sodium in the broth helps the body to retain fluid (3). On average, a 120ml serving provides around 200mg of sodium, which is more than three times the amount in the average gel (3).

Amino acid content in broth

The exact levels and ratios of amino acids found in broth and how nourishing it is, depends on the type of broth, recipe, sourcing of ingredients, its concentration and other factors. For example, lamb and beef shanks are richer in bone marrow than poultry broth, where the bones are lighter and thinner. On the other hand, veal bones from calves generally have more collagen and cartilage than bones from grown cows.

There are four main amino acids found in broth:

Proline
This amino acid is used to promote healthy collagen and cartilage. Morell, by placing individuals on a proline-free diet, observed that the body is unable to produce sufficient quantities of proline without dietary assistance (1).

Glycine
The body requires glycine for healthy blood, fat digestion and detoxification. It plays an important role in the synthesis of haemoglobin, creatine, porphyrin, bile salts, glutathione, DNA and RNA. Glycine can decrease inflammation throughout the body and also contributes to gastric acid secretion.

Morell states that the human body requires high amounts of glycine to aid the detoxification of heavy metals, pollutants and industrial chemicals (1). Therefore, with so many important metabolic functions, glycine needs to be readily available. The body is able to make glycine, but Morell indicates that even a healthy being may not be able to make enough glycine during periods of high stress, including heavy training (1).

Glutamine
Ideally, glutamine is produced abundantly by our muscles and circulates throughout the body where it is needed. However, athletes’ glutamine stores deplete rapidly from the physical stress endured through intense exhausting exercise, overtraining or injury. If the glutamine stores are not replenished quickly enough, muscle atrophy begins. One study observed that the blood glutamine levels of marathon runners post-event dropped by 20 per cent (4). Glutamine is the third highest amino acid found in broth and gelatine, suggesting that broth would be a good supplement for athletes, especially if consumed directly after a race.

Together with proline and glycine, glutamine enhances the recovery from injuries and wounds. Studies have shown that increased glutamine supplementation decreases the recovery period during times of injury (5): “it is a popular supplement for overtraining syndrome, in which the overworked body cannot produce enough glutamine on its own.” Diminishing glutamine levels can also expose the athlete to a higher rate of infection, further justifying its importance.

Alanine
This amino acid is involved in liver function, glycolysis, gluconeogenesis and the Krebs cycle. It is made by the body, but many athletes and bodybuilders supplement for enhanced endurance capabilities and muscle hypertrophy.

Conclusions

It would be wonderful to find evidence for the efficacy of broth in sport; however there are not many studies due to its batch uniqueness. Science likes consistency, so this valuable superfood is overlooked because of the many uncontrollable variables. “Science today follows the money and unless something can be pilled, powdered and patented, it’s not likely to be investigated (6).” Tradition, however, tells us that bone broth is nourishing and making it yourself with a high proportion of cartilage should give you the best benefits.

- References available upon request