Anabolics encourage the body to build muscle tissue. Growth and sex hormones are natural anabolics, necessary for normal growth and development. Synthetic anabolics aren’t bad in and of themselves. They help debilitated animals, such as horses recovering from malnutrition, prolonged illnesses, severe injuries and even the ravages of old age. In these conditions, synthetic anabolics help the horse’s body build muscle tissue rather than burn it and help make better use of available nutrients.
Unfortunately, this valid use of synthetic anabolics has been perverted to the point that more are sold and used to create unnaturally pronounced muscular development in sales yearlings or beef up performance horses. This is simply the easy way out, and it’s the horses who end up paying the price.
Anabolic-steroid abuse is associated with multiple side effects. The most familiar in human steroid abuse is “steroid rage,” those horror stories of young men becoming increasingly aggressive and out of control. The same thing happens to a high percentage of horses given anabolic steroids. In fact, this increased aggressiveness is considered desirable by some trainers.
Less well known, but equally serious, is the effect on growing bone. Young animals given anabolic steroids experience premature closure of the growth plates. Not only are they shorter than they should be, the horse’s bone may be inadequate to support its actual body structure.
Tendon and ligament injuries are common in humans abusing steroids. Experts believe this occurs because the drugs stimulate rapid and dramatic muscular development but without a matching increase in size and strength of the attached tendons and ligaments. Although no one has studied it, it’s likely the same thing occurs in horses.
Internal organs also suffer. Anabolic steroid abuse can damage the heart and the liver. They have a negative effect on the reproductive system. Testicles shrivel, ovaries stop cycling and infertility results. If the abuse began early in life, infertility can be permanent.
Proper Muscle Building
Instead of using synthetic steroids, diet and exercise — those boring basics — are the way to build a strong, muscular athletic horse.
Start with your horse’s protein intake, and we mean total dietary protein, not just what the feed bag claims. A 10% total dietary protein is adequate for adult maintenance and light work, 12 to 14% for higher performance, 14 to 16% for growth.
Levels of key amino acids are also crucial. Lysine leads in importance for growth and development. Requirements vary from 23 g/day for adult maintenance (1,100-lb. horse) to 50 g/day for an 18-month-old “yearling” in training.
Also important to growth and development are the sulfur-containing amino acids, methionine, cystine and cysteine. Actual requirements are unclear but are estimated to be around half of the lysine requirement.
With exercise, the branched-chain amino acids (valine, leucine and isoleucine) also enter the scene. Muscle can use these as fuel, sparing carbohydrate stores, and the metabolites — other amino acids — play a role in many important functions, which include hormone production and regulation, maintenance of a strong immune system and conversion to glucose.
Carbohydrates and fats are the primary sources of energy. Carbohydrates come from grain, grass and hay. Fats come from grains, small amounts in grasses and any added supplementation. Actual fat requirements for growth, development, hormone production and exercise are low for horses, around 2% of the total calories in the diet. Fats and carbohydrates have no specific anabolic effect beyond providing the calories needed to fuel the body.
Vitamins and minerals, while important to your horse’s optimal diet, also don’t play a magical role in making your horse bigger, stronger or faster. However, deficiencies will result in metabolic inefficiency and likely put on fat rather than build muscle. (Chromium has been reported to assist building muscle instead of fat in both humans and animals, but this effect is more likely related to the fact that modern diets are often critically low in chromium in the first place.)
Once the needs for growth and maintenance are met, exercise determines whether your horse will put on muscle and build better bone/joints or simply get fat. Exercise favors building and remodeling of tissues through a complicated system of checks and balances, mediated by hormone release. For example, the exercising muscle releases large quantities of amino acids, including glutamine, an amino acid that helps build a strong immune system. In turn, glutamine can trigger a growth-hormone release.
Activation of the centers of the brain that control movement, as well as nerve impulses generated by exercising muscles, also trigger the brain to release growth hormone. Growth hormone in turn is converted to “insulin-like growth factor” or IGF. IGF stimulates the uptake of nutrients by the muscle cell and the building of muscle.
A number of nutritional supplements claim to duplicate one or more of the effects of anabolic steroids. Some focus on muscular development and/or fat burning, others on metabolic efficiency, still others on manipulating hormone releases. While we are not advocating these supplements as replacements for proper diet and exercise, they can be properly used to help facilitate growth and development.
For our trials, we looked at both growth and development in young horses not yet in work (weanlings to two-year-olds), as well as active performance horses of various ages. Since the goals of someone finishing a yearling for the sales or show ring are quite different from those of a conditioning trainer, we applied somewhat different standards to these two groups.
Sales/Halter Horses: Our favorite product for sale and halter horses is Body Builder from Equi-Ade, a microcrystalized gamma oryzanol in oil suspension. The most obvious results were noted in geldings. When kept on the same base diet, horses receiving the gamma oryzanol carried more weight in general and had fairly good muscular definition. Similar results were obtained on a test horse with Body Pro II from United Vet Equine.
We had disappointing results with the powdered gamma oryzanols, even the more potent formulation in Gamma Oryzanol Ultra Pure from Gateway. One horse showed improved weight gain and muscle definition compared to his unsupplemented condition, but it was not as dramatic a change as with the liquid gamma oryzanols. However, our test horse had been sick for two weeks before the study was started, so it’s unclear if this produced an effect or not.
Similarly, one of two horses on United Vet Equine’s Profile seemed “beefier” than his presupplement condition but not to the same degree as the response with the liquids.
Equibol, a unique derivative of a beneficial strain of probiotic organism, proved beneficial to one youngster who was having trouble gaining weight and appeared to have a heavy parasite infestation despite rigorous dewormings. His big belly disappeared, coat quality improved, muscling and general body condition improved. Another weanling who was already gaining and growing well on a high-quality diet showed no improvement.
Creatine supplementation of these young horses had no visible effect.
Performance Horses: The amino-acid-based specialty products were hands-down leaders for anabolic alternatives in our performance horses.
Beta-Advantage from Metabolic Technologies contains a metabolite of the branched-chain amino acid leucine-?’-hydroxy- ?’-methylbutyrate (HMB for short). Leucine is the most metabolically active of the BCAAs in the muscle.
HMB supplementation at one packet twice a day in the horse’s feed resulted in rapid increases in muscling and a parallel loss of body fat. The muscle was also of excellent qual ity, well defined but pliable. Trainers were impressed with the low level of muscle soreness and the ease with which they progressed through training.
Research on HMB in horses confirms improvement in red-blood-cell parameters, lower levels of urea in the blood (blood urea is an indicator of protein breakdown), better maintenance of blood glucose levels during exercise and prevention of the training-induced drop in cholesterol seen in the control horses.
A group of racehorses followed through the duration of a track meet showed lower levels of muscle enzymes in the blood, held their weight better, had higher globulin (immune protein) levels and a higher win percentage than unsupplemented control horses.
Similar beneficial effects on muscle metabolism have also been proven for the BCAA supplement BC2A. This product was previously called Pro-Burst (see Tying-Up, April and May 1998) and is now only available through veterinarians. Horses supplemented with BC2A prior to exercise showed similar muscle characteristics as those we supplemented with the HMB but did not have as rapid a loss of body fat. Some additional improvement was noted in terms of muscle size and definition in one of two horses given double dosing, one hour before and one hour after exercise.
We did a crossover field test comparing the two products, trying a horse that had been on Beta-Advantage next with BC2A and two that had been on BC2A next with Beta-Advantage. One month between supplement trials was given. The horse that had been on Beta-Advantage first did equally well on a double-dose schedule of BC2A but did not show the improved muscle definition with the single pre-exercise dose (quality of muscle, however, was excellent on both horses).
Of the two who were switched to Beta-Advantage, one showed no detectable difference while the other developed better muscular size and definition as well as a clear loss of body fat.
One drawback we found with Beta-Advantage and BC2A was that horses in early training that had received either supplement were noted to rapidly lose the muscular development when supplementation was stopped. This effect was not as noticeable when supplemented horses were already race fit. We were able to prevent this return to presupplement body condition in one horse by timed feeding of one packet of Beta Advantage given one hour before work.
We also had visible but less dramatic improvement in muscling and loss of body fat using GH-4 from Uckele. This product contains L-arginine, an amino acid that is known to cause growth hormone secretion, as well as all the cofactors known to be needed for the processing of arginine by the brain (choline and B-6). Supplementation at a rate of 40 to 60 grams per day resulted in improved alertness, better muscle definition and reduced muscle soreness.
Note: When using this product, follow manufacturer’s recommendations precisely with regard to how long to feed and periods off the supplement. Timing of the dose (before exercise or before sleep) is critical to getting the effect, as is administering it on an empty stomach. Dissolve in water immediately before use and give by dose syringe.
Our previous experience with creatine supplements was equivocal at best (see March 1999). This time, we may have found an exception in Amino Blast II from Uckele. In addition to creatine, it contains glutamine (an amino acid lost in great amounts during exercise), lipoic acid (a cofactor that improves energy generation in the muscle) and the amino-acid tyrosine (thought by some to improve the capacity for short bursts of explosive speed but unsupported by formal research).
Two of four horses receiving this supplement showed a response similar to what is described with creatine in humans — improved sprint speed. We’re not sure whether this was due to the combination of ingredients or a result of one or more ingredients working in synergy that produced the effect.
Equibol, from Equibol AC, contains an active ingredient prepared from cultures of the same beneficial probiotic organism found in Kefir, the legendary yogurt-like drink associated with longevity.
Studies have shown that this extract limits the activity of intestinal bacteria that break down protein, increasing the protein availability of the diet. It has also been proven to result in better glycogen stores in the muscles.
As with our young halter horses, good results were seen in horses with a history of intestinal problems (bloating, intermittent diarrhea). Reduced abdominal size, better coat and better overall body condition were noted.
Uckele Health’s Gelding Builder is a mixture of Mexican yam (plant sterols with estrogenic activity) and bovine testicular tissue. We tried it on three geldings, equine equivalents of the proverbial 90-pound weakling.
We didn’t see changes as great as with HMB, but we did note better muscling after four to six weeks on two horses. Most obvious in our test horses were attitude changes. They were more alert (although not more aggressive) and interested and showed increased appetites.
If you want stronger, well-muscled babies and performance horses, start with a professional analysis by a nutritionist or veterinarian of your feeding program. It’s a wise investment.
Take a good look at your horse’s work schedule, too, remembering that the best stimulus to muscle development is exercise.
For youngsters that still don’t fill out well on an otherwise optimal diet and exercise, Body Builder is our first choice as an anabolic steroid alternative nutritional supplement.
For older performance horses, we couldn’t beat the results from Beta-Advantage. The combination of fat loss, enhanced muscling and performance was unbeatable.
Similar benefits (except for enhanced fat loss) were seen with BC2A paste, but this was more expensive than the already pricey Beta-Advantage. Our choice for Best Buy is Uckele Health’s GH-4. Fat loss was also excellent with this product and muscular development, although not as pronounced as with Beta-Advantage or BC2A, also good.
Also With This Article
Click here to view “Growth Hormone Abuse.”
Click here to view “Supplement Alternatives To Anabolic Steroids.”
Click here to view “Gamma Oryzanol Precaution.”
Click here to view “Building Muscle While Burning Fat.”
Click here to view “Immunity.”
Click here to view “Overtraining And Catabolism.”