Table 1.
Studies assessing effects of collagen supplementation on joint pain and recovery from joint injuries
| Study | QACIS score | Participants | Type and dosage | Exercise modality | Outcome measures | Main findings |
|---|---|---|---|---|---|---|
| Clark et al. (2008) | 78.57% |
97 varsity team or club sport level athletes with activity-related joint pain (45 males, 52 females) (20 ± 1 years) |
10 g/day collagen hydrolysate | Continued routine sporting activity for 24 weeks |
VAS for joint discomfort Physician’s assessment of joint discomfort |
↓ in joint pain with COL vs PLA ↓ joint pain at rest (p = 0.025), walking (p = 0.007), standing (p = 0.011), carrying objects (p = 0.014) and lifting (p = 0.018) ↓ in alternative therapies in COL vs PLA (12 vs 39 times, from baseline) |
| Lugo et al. (2013) | 85.71% | 55 participants with joint discomfort on doing physical activity (46 ± 2 years COL, 47 ± 2 years PLA) | 40 mg/day of undenatured type II collagen derived from chicken sternum | Step-mill exertion test after 4 months | Knee flexion and extension to assess joint function |
↑ in knee extension with COL vs PLA (p = 0.011) ↑ in length of pain-free strenuous exertion with COL from baseline (2.8 ± 0.5 min vs 1.4 ± 0.2 min; p = 0.019) |
| Zdzieblik et al. (2017) | 92.86% |
139 athletic participants (56 males, 83 females) (24 ± 0.3 years) |
5 g/day of collagen peptides | Regular exercise, at least 3 h per week for 12 weeks |
VAS for pain at rest and during activity Joint mobility through range of motion methods. Both evaluated by a physician |
↓ in knee pain seen in both groups (p < 0.001), but reduction was more pronounced in COL group as compared to PLA (38.4 vs 27.9%, respectively) on VAS scale ↓ in alternative therapies in COL vs PLA (59 vs 40%, from baseline) |
| Dressler et al. 2018 | 71.43% |
50 athletic participants (24 males, 26 females) (27 ± 9 years) |
5 g/day of collagen peptides | 3 home-based exercise sessions per week for 6 months (rope-skipping, squats and one-legged heel raises) |
CAIT—a self-reported questionnaire FAAM-G questionnaire Ankle arthrometer to measure ankle stiffness |
↑ in perceived ankle function in COL CAIT score ↑ by 5.28 ± 1.16 in COL (p < 0.001) No change in CAIT score was analysed in the PLA |
| Praet et al. (2019) | 85.71% |
20 participants with Achilles tendon symptoms (12 males, 8 females) (44 ± 8 years) |
5 g/day of collagen peptides | Eccentric calf-strengthening programme performed daily for 6 months |
VISA-A questionnaire Real-Time Harmonic Contrast Enhanced Ultrasound to measure tendon thickness |
COL may ↑ the clinical benefits of a well-structured calf-strengthening and return-to-running program in Achilles tendinopathy patients ↑ VISA-A score in COL (12.6 points) vs PLA (5.3 pts), and ↑ (17.9 vs 5.9 pts) after crossing over |
| Average QACIS score | 83% |
VAS Visual analogue scale, COL Collagen peptide supplementation, PLA Placebo, CAIT Cumberland Ankle Instability Tool, FAAM-G Foot and Ankle Ability Measure German version, VISA-A Victorian Institute of Sports Assessment–Achilles, ↑ increased, ↓ decreased