Background The application of dry needling usually is associated with postneedling‐induced pain. A postneedling intervention to reduce this adverse event is needed. Objective To determine the effectiveness of low‐load exercise on reducing postneedling‐induced pain after dry needling of active trigger points (TrPs) in the infraspinatus muscle in subacromial pain syndrome. Design A 72‐hour follow‐up, single‐blind randomized controlled trial. Setting Urban hospitals. Participants Individuals with subacromial pain syndrome (n = 90, 52% female, mean age: 35 ± 13 years) with active TrPs in the infraspinatus muscle. Interventions All individuals received dry needling into the infraspinatus active TrP. Then, they were divided randomly into an experimental group, which received a single bout of low‐load exercise of shoulder muscles; a placebo group, which received inactive ultrasound for 10 minutes; and a control group, which did not receive any intervention. Outcome Measures Numerical Pain Rating Scale (0‐10 point) was administered postneedling, immediately postintervention (2 minutes), and 24, 48, and 72 hours after needling. Shoulder pain (Numerical Pain Rating Scale, 0‐10) and disability (Disabilities of the Arm, Shoulder and Hand; Shoulder Pain and Disability Index) were assessed before and 72 hour after needling. Results The 5 × 3 analysis of covariance showed that the exercise group demonstrated a larger decrease in postneedling‐induced pain immediately after (P = .001), 24 hours (P = .001), and 48 hours after (P = .006) than placebo or control groups. No differences were found at 72 hours (P = .03). Similar improvements in shoulder pain (P < .001) and related disability (Disabilities of the Arm, Shoulder and Hand: P < .001; Shoulder Pain and Disability Index: P < .001) were observed 72 hours after needling, irrespective of the treatment group. Conclusions Low‐load exercise was effective for reducing postneedling‐induced pain on active TrPs in the infraspinatus muscle 24 and 48 hours after needling. The application of a postneedling intervention did not influence short‐term pain and disability changes. Level of Evidence I