Flexible is a simple but complete formula containing all the standard joint health ingredients (Glucosamine, Hyaluronic Acid, etc.)…
Glucosamine is a member of the group known as ‘amino sugars’, and has been studied primarily in regards to joint health. Glucosamine is commonly found in two forms: glucosamine sulfate and glucosamine hydrochloride. Glucosamine sulfate appears to be the most readily absorbed when consumed orally.
While originally thought to directly induce collagen synthesis, more recent research indicates that glucosamine may actually work by inhibiting Interleukin-1, a protein which regulates inflammatory response and ultimately breaks down collagen. By inhibiting IL-1, glucosamine may reduce inflammation and slow down the degradation of collagen, thereby preserving the joint and possibly reducing joint pain.
This was evidenced in a recent 2013 study, as well as a 2009 study which noted lower levels of CX-II (a bio-marker of collagen breakdown) in athletes (bicyclists and soccer players) following glucosamine supplementation (most effective at 3 grams daily). While glucosamine appears to be atleast somewhat effective at preserving joints, there is no evidence to suggest that supplementation can reverse osteoarthritis (degradation of joints). However, preserving joints is still of much importance to athletes (particularly high impact sports) who may be in danger of developing osteoarthritis.
Overall, glucosamine may certainly benefit those suffering from osteoarthritis (or perhaps less severe joint degradation), but the miracle claims made by some supplement companies are a bit exaggerated. Flexible contains 750mg of glucosamine sulfate per (2 capsule) serving which, when taken twice daily, achieves the minimum effective dose of 1500mg glucosamine daily. Users may choose to double the dose in order to achieve maximum efficacy. Glucosamine is remarkably safe at these levels.
Chondroitin, a major component of cartilage, is generally seen along-side glucosamine in joint supplements based on the belief that the two work synergistically together to reduce inflammation and repair joints. In vitro, chondroitin and glucosamine have been demonstrated to synergistically induce collagen synthesis.
However, in vivo studies comparing and contrasting the effects of chondroitin relative to glucosamine fail to find such synergy between the two. In fact, most of the benefit obtained from supplementation with glucosamine and chondroitin is thought to be from glucosamine as chondroitin has shown little promise when studied in isolation.
Methylsulfonylmethane (MSM) is similar in efficacy to glucosamine, but a significant synergistic effect has never been recorded. It is hypothesized that the real benefit of MSM lies in the fact that it contains sulfur, which is a component of collagen, and thus necessary for functional, healthy joints. According to this hypothesis, only people with sulfur deficiencies would derive benefit, and would be able to derive the same benefit from other sulfur containing compounds such as the amino acids methionine and cysteine.
However, this is just a hypothesis and an exact mechanism of action is not currently known. Overall, it appears MSM offers the same benefits as glucosamine in regards to joint health, but there is no evidence that the same benefit cannot be derived from glucosamine supplementation alone.
Like glucosamine, hyaluronic Acid is a major constituent of synovial fluid, the body’s natural joint lubricant. It has been studied primarily as a potential treatment for joint pain, and while a significant analgesic (painkiller) effect has been noted in rats following injections with hyaluronic acid, similar treatment has only been mildly effective in humans suffering from osteoarthritis of the knee. While most studies have used injection, a 2012 study published in “The Scientific World Journal” found that oral supplementation with 200mg hyaluronic acid daily over a 12 month period improved symptoms in subjects suffering from osteoarthritis of the knee.
However, these results were far from miraculous and it should be noted this particular study combined the treatment with a quadriceps strengthening exercise regimen. Ultimately, hyaluronic acid injections appear to be more effective at reducing joint pain than oral supplements. While some efficacy has been noted with oral HA supplements, it’s tough to say whether this same pain relief could be achieved with a simple OTC pain medication. As far as a synergistic effect between HA and glucosamine, more studies are needed.
Cissus Quadrangularis is a plant found in Africa and parts of Asia. It has a long history of use by the inhabitants in the areas it is indigenous to, but has recently made its way into fitness supplements. It is alleged to have anti-inflammatory, analgesic (pain relief), and antioxidant properties. Of particular interest is Cissus Quadrangularis’s effects on bone health.
A 2003 study in the Journal of Ethnopharmacology found that the extract possessed “a definite antiosteoporotic effect” in rats. For anyone who suffers from a bone debilitating disease such as osteoporosis, this is good news, but Cissus has implications for athletes as well. While it has proven effective in decreasing recovery time from bone injury, it does so by influencing early regeneration of connective tissue, meaning it may be beneficial for joints as well.
While more studies are needed to focus directly on the effects of Cissus supplementation on connective tissue, these findings certainly imply benefits for bodybuilders and athletes whose joints are constantly under stress. One human study found that subjects with exercise related injuries who recieved 3200mg of Cissus Quadrangularis extract over an 8 week period reported a decrease in joint pain. However, given that the nature of the results was somewhat subjective, further study is needed to determine a more objective mechanism of action.
THE BOTTOM LINE:
Flexible contains the usual joint health supplements: glucosamine, chondroitin, MSM, and hyaluronic acid, but with the addition of Cissus Quadrangularis. Ultimately, Flexible may offer some benefit to those suffering from osteoarthritis, or those in danger of developing osteoarthritis. However, this benefit may be attributed primarily to glucosamine, as the other ingredients have much less validity to them.
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