This study evaluates the effect of short-term load restriction following autologous whole-blood injection (AWBI) in plantar fasciitis patients. Given that AWBI induces an inflammatory healing response, restricting weight-bearing in the initial phase may optimize recovery. A prospective, single-blind randomized controlled trial was conducted with 149 patients unresponsive to two months of conservative treatment. Patients were randomized into two groups: a load restriction group (n = 75) instructed to avoid weight-bearing for three days, and a non-load restriction group (n = 74) who resumed normal walking immediately. Visual Analog Scale (VAS) pain scores and Pressure Pain Threshold (PPT) were assessed at baseline, days 3, 30, 90, and 1 year post-treatment. Analgesic use and return to daily activities were also recorded. At day 3, the load restriction group reported significantly lower VAS pain scores (8.23±0.7 vs. 8.49±0.5, p = 0.010) and higher PPT values (238.9 ± 36.9 vs. 216.4 ± 45.4, p = 0.001) than the non-restricted group. At day 30, these differences remained significant (VAS: 5.53±0.9 vs. 5.99±0.9, p = 0.002
PPT: 432.6 ± 43.5 vs. 411.4 ± 58.8, p = 0.014). The load restriction group required fewer analgesics (p <
0.001) and returned to daily activities sooner (4.2 ± 0.4 vs. 5.9 ± 1.5 days, p <
0.001). By day 90 and 1 year, no significant differences remained. A three-day weight-bearing restriction post-AWBI significantly enhances early pain relief and functional recovery, reduces analgesic dependence, and accelerates return to daily activities. Given its ease of implementation and cost-free nature, this approach can be readily integrated into routine clinical practice for plantar fasciitis patients undergoing AWBI to fasten recovery. LEVEL OF CLINICAL EVIDENCE: Level 1.