Is it just a coincidence that bodybuilders are more likely to suffer injuries because of heavy training, or does the use of anabolic steroids have any impact on tendon/collagen strength? The research is very preliminary, as only a few studies have examined the effects of anabolic steroids on tendon and collagen strength. It was shown that anabolic steroids alter the biomechanical properties of tendons and reduce tendon flexibility.
Some interesting theories have been suggested as why heavy anabolic steroid use can cause tendon injury, which is based around cortisol production and anabolic steroids. Researches have demonstrated that anabolic steroids combined with tension overload reduced MMP2 activity (MMP2 is a gene responsible for collagen production) and increased serum values of cortisol. During cortisol treatment, the serum levels of genes responsible for collagen production decrease, suggesting that cortisol suppresses the synthesis of collagen production. The reduction in genes for collagen and tendons have been speculated as to why anabolic steroids makes bodybuilders susceptible to injuries. New research links the use of high doses of anabolic steroids to tendon and collagen dysfunction, which may make a bodybuilder think twice about training heavily while using anabolics.
Researchers examined how heavy use of the anabolic steroid Deca-Durabolin affected collagen strength in rats. The rats were separated into two groups: natural training and training with heavy anabolic steroid use. The dose the researchers administered to the rats was considered supra-physiological – Deca-Durabolin (nandrolone decanoate) 5mg/kg of bodyweight.
The rats were cleverly forced to perform resistance exercise, but you can’t just tell a rat to start benching – so the researchers attached weights to the rats’ backs. They dropped the rats into a tank of water and the rats immediately jumped out of the water as soon as they were dunked. Every week, the researchers gradually made the weight on the rats’ backs heavier and heavier until at the end of seven weeks the weight was 80 percent of their bodyweight. The researchers dropped the rats in the tank so that they performed this for 4 sets x 10 repetitions of “jumps” with 30-second rest periods. After that, they rats were sacrificed and the rats’ tendons and collagen were examined for gene expression.
There were some very interesting findings after seven weeks of training with anabolic steroids, compared with the natty (natural) group of rats. The natty group did not have any biochemical changes in the rat tendon/collagen properties, while the anabolic steroid group had major changes. The Deca-Durabolin group had reduced biochemical properties of genes involving tendon and collagen strength.
It is interesting to note that anabolic steroids administration reduced the accumulation of IGF-1 mRNA levels in some tendon regions, compared to the non-treated, trained group. This decrease of IGF-1 mRNA levels induced by AAS administration may be related to the observed decreases collagen expression when considering the possible connection between IGF-1 and collagen synthesis. The anabolic steroids treatment also decreased the MMP-2 mRNA expression (this gene encodes an enzyme for collagen).
The above study is similar to another recently published study, which showed that nandrolone impaired the healing of rotator cuffs of rabbits. In the latter study, male rabbits underwent an incision in the rotator cuff and were divided into groups with anabolic steroids (nandrolone decanoate, 10mg/kg) and natural recovery. Groups that did not receive anabolic steroids showed better healing and more tendon strength compared to groups that received anabolic steroids. Microscopic examination of specimens from the groups with anabolic steroid use showed focal fibroblastic reaction and inflammation, suggesting an impaired healing response.
The key point is that many of these studies were using supraphysiological dosages of steroids that could be like the typical Olympia stack – but the new research suggests that a high-volume approach to training with less weight may be a better approach to use for a bodybuilder than a high-intensity, heavy weight program that puts more stress on the tendons and makes them more susceptible to injury.