The increase in the prevalence of long-term joint injuries and osteoarthritis from sport participation is unquestionable and troubling.
In light of this, recent scientific research has involved specific exercise protocols combined with the ingestion of Hydrolysed Collagen (HC), and examined the impact on joint functionality during activity and recovery.
Scientists now believe that it is likely that exercise would aid the benefits of ingested HC due to the ‘mechano-transduction’ hypothesis, which proposes that mechanical loading of tendon tissue during exercise creates a signaling cascade in the tissue cells that increases production of matrix proteins and subsequent tendon size and strength.
In September 2021 a systematic scientific review, (The effects of collagen peptide supplementation on body composition, collagen synthesis, and recovery from joint injury and exercise), was published in the Journal of Amino Acids and examined the effects of HC on exercise performance, recovery, and rehabilitation in the elderly, and elite and recreational athletes.
The review aimed to evaluate the current literature available on the combined impact of ingesting HC in conjunction with an exercise program. It set out to evaluate the effect on joint function and athletic recovery, and gauge appropriate dosing strategies. The systematic review included parameters such as: joint function, muscle and joint injury recovery, body composition, muscle protein synthesis (MPS) and collagen synthesis.
Fifteen randomised controlled trials were selected after screening 856 articles. The study populations included 12 studies in recreational athletes, 2 studies in elderly participants and 1 in untrained pre-menopausal women. Study outcomes were categorised into four topics: (i) joint pain and recovery from joint injuries, (ii) body composition, (iii) muscle soreness and recovery from exercise, and (iv) muscle protein synthesis (MPS) and collagen synthesis.
Of these 15 eligible studies, 8 used HC in doses of 5–15 g/day, 1 used 20 g/day, 1 used 30 g/day, 1 used 60 g/day, 2 used gelatine in doses of 5 g/day and 15 g/day and 2 used original supplements containing 40 mg/day and 3 g/day of collagen peptide.
All the trials were conducted between 2005 and 2019. There was a total of 656 participants, with 325 males and 276 females. Twelve studies had recreationally active participants (average age: 30±10 years) who experienced joint-related discomfort, 2 studies were in an elderly population; 1 in men experiencing onset of sarcopenia (age 72±5 years) and the other in healthy, older women (age 69±3 years), and 1 study was in untrained pre-menopausal women (age 40±8 years).
None of the studies reported conflicts of interest.
Effects of collagen supplementation on joint function and recovery from joint injuries
Five studies met the criteria and all reported beneficial effects of HC in reducing joint pain, improving joint function, increasing the length of pain-free strenuous exertion, and reducing the need for alternative therapies, especially when combined with an exercise rehabilitation programme.
Both Clark and colleagues (2008) (10 g/day Peptan) and Zdzieblik et al.(5 g/day) observed that HC led to a decrease in activity-related joint discomfort and use of alternative therapies to manage pain. A possible explanation for the reduction in joint pain may be that HC increases type I, II, IV collagen, proteoglycan, and elastin synthesis in the articular cartilage, possibly reducing tissue damage and decreasing pain.
Collagen peptide supplementation may also aid formation of Extra Cellular Matrix (ECM) molecules leading to increased firmness of the connective tissue, and downregulation of the enzymes that degrade ECM collagen proteins.
Moreover, collagen peptides may possess anti-inflammatory properties, as glycine (the amino acid found in abundance in HC) can inhibit pro-inflammatory cytokine release.
Young athletes had improved ankle function with HC, citing a lower feeling of the ankle ‘giving away’ and a decrease in reoccurrence of ankle injuries after suffering from chronic ankle instability.
Similarly, one study coupled HC with an eccentric bi-daily calf strengthening and a return-to-running exercise protocol in athletes suffering from Achilles tendinopathy. The participants were able to return to running after the treatment but did not reach pre-injury levels within the duration of the study.
The 22% glycine content of HC is known to enhance collagen matrix organisation strength, reduce inflammation and influence tenocyte metabolism in tendons (Vieira et al. 2018).
Effects of collagen supplementation on body composition
Four studies evaluated the effects of collagen supplementation on body composition and/or muscle strength, using collagen or a placebo (PLA) coupled with a resistance training exercise program. One study was conducted in elderly sarcopenic men (15 g/day HC for 3 months), two studies were in recreationally active men (15 g/day HC for 3 months) and one study was in untrained pre-menopausal women (15 g/day HC for 3 months).
One study found a greater increase in fat free mass (FFM), decrease in body fat percentage (BF), and an increase in hand-grip strength, with participants who took HC.
Another study noticed a significant increase in FFM with HC, and there was a significant increase in body fat mass with PLA . Another study in recreationally active men found a significant decrease in body mass and increase in FFM with HC, whereas no change was observed in fat mass (FM) for either HC or PLA.
Taking HC in conjunction with a resistance training programme induced significant changes in elderly sarcopenic men.
Two studies observed a significant increase in FFM with HC. The changes in FFM are possibly attributed to an increase in surrounding connective tissue. Previous studies have also observed an increase in ECM synthesis in connective tissue with HC supplementation.
For changes in FM, HC has shown to reduce body weight gain and body fat. HC induced a higher increase in proteins (such as myosin proteins, actin-binding proteins and tropomyosins) related to resistance training adaptations, likely due to the high hydroxyproline-peptide concentration in collagen peptide supplements as observed in other studies (Kitakaze et al. 2016).
Furthermore, a higher increase in myotilin, a muscle Z-disk protein, which is an important marker for myofibril remodeling post-exercise, was observed in the HC group. The higher upregulation of proteins with resistance training and HC indicates a deeper effect on skeletal muscle proteomes as compared to resistance training solely.
Collagen supplementation combined with resistance training elicited moderate improvements in body composition. The increase in fat-free mass is purportedly due to HC’s effect on the surrounding connective tissue, and not myofibrillar protein, as there were no changes observed in muscle fiber.
Effects of collagen supplementation on muscle soreness and recovery from exercise
Two studies assessed the effect collagen supplementation had on subsequent exercise performance and recovery from muscle soreness. The studies were conducted in recreationally active men. One study used 3 g/day HC for 6 weeks and the other used 20 g/day HC for 7 days, prior to their respective muscle damaging exercise protocols.
A moderate effect size on perceived recovery and discomfort, and a strong effect for ‘pain with movement’ was observed following HC. Similarly, a large effect size on muscle soreness with HC was detected 24 h and 48 h post-exercise by Clifford and colleagues (2018) using the bioavailable collagen Peptan.
Collagen peptides seemed to attenuate decrements in bench-press performance, improve recovery, and reduce symptoms of delayed onset of muscle soreness.
Plasma biomarkers for muscle damage and inflammation were also lower in the HC group.
A higher tolerance for repeated high-intensity resistance exercise protocol in the intervention group was observed, demonstrating that HC may accelerate the protective adaptation of the ‘repeated bout effect’, allowing for enhanced musculoskeletal recovery by possible ECM remodeling.
Clifford et al. (2019) found HC to reduce muscle soreness post-exercise on a visual analogue scale.
Effects of collagen supplementation on collagen synthesis and muscle protein synthesis
Four studies assessed the effects of HC on bodily collagen synthesis and muscle protein synthesis.
Shaw et al. found that collagen synthesis increased and remained elevated for 72 h, with 15 g/day HC enriched with vitamin C as compared to a 5 g/day dose and PLA. The amino acid content of blood peaked 1 h after 15 g HC consumption (increase of 376 mmol/L in glycine, and 162 mmol/L of proline vs baseline) and 30 min after 5 g HC, providing important information regarding exercise timing in accordance with the collagen dose.
The 15 g/day HC augmented collagen synthesis in the recovery period after exercise as seen by the increase in bone collagen synthesis markers (153% increase with 15 g HC, vs 59.2% increase with 5 g HC and 53.9% increase with PLA).
This indicates that the improved collagen synthesis with 15 g/day HC coupled with an intermittent exercise protocol, consumed 60 minutes prior to exercise, may improve tissue repair and help prevent injuries.
So in summary, the review found
- Strong evidence of 5–15 g/day dose of HC in improving joint pain and functionality.
- Changes in body composition and strength with 15 g/day HC and resistance training were more prominent in elderly sarcopenic men than they were in in young recreationally active participants.
- Exercise and vitamin C seemed to aid collagen synthesis. 15 g/day HC was more effective than 5 g/day HC in elevating collagen synthesis, hence 15 g/day may be a more effective dose. HC should be consumed prior (~60 min) to exercise to maximise collagen synthesis.
- Muscle recovery had a modest but significant improvement with HC.
Collagen synthesis rates were elevated with 10-15 g/day HC.
CollagenX uses Peptan exclusively in all their collagen products. Peptan Hydrolysed Collagen is most beneficial in improving joint functionality and reducing joint pain.
CollagenX Hydrolysed Collagen improves body composition, strength and muscle recovery.