Platelet-Rich Plasma (PRP) therapy is a regenerative treatment that utilizes a patient’s own concentrated blood components to accelerate healing in injured tissues like tendons, ligaments, and joints. Blood is processed to isolate platelets, which are rich in growth factors, and this concentrated solution is injected directly into the site of injury. This procedure stimulates the body’s natural repair mechanisms, restarting the healing process in chronic or slow-to-recover areas. Adherence to the post-injection protocol is crucial for success, and active patients often ask when it is safe to resume physical activity.
The Initial Phase of Rest and Protection
The first phase following a Platelet-Rich Plasma injection focuses on strict rest and protecting the treated area, typically spanning the first three to five days. Immediately after the procedure, patients must avoid any strenuous activity, heavy lifting, or high-impact movements that could disrupt the newly injected plasma. This period allows the concentrated platelets to settle and release their growth factors, which initiates the necessary inflammatory cascade for tissue repair.
Pain management during this initial phase is important, and patients must be careful about which medications they use. Non-Steroidal Anti-Inflammatory Drugs (NSAIDs), such as ibuprofen or naproxen, should be strictly avoided for at least two to four weeks post-injection. NSAIDs interfere with the cyclooxygenase (COX) enzymes, which are essential for the inflammatory response that PRP is intended to trigger. By inhibiting this initial inflammation, NSAIDs can potentially negate the therapeutic effect of the PRP treatment itself.
Instead of NSAIDs, over-the-counter pain relievers like acetaminophen are recommended for managing discomfort because they do not interfere with the inflammatory pathways necessary for PRP activation. Some discomfort, and even mild swelling, is a normal and expected sign that the healing process has begun. Limiting movement of the treated area to basic daily tasks for the first 48 hours is usually advised to give the injected solution time to integrate with the damaged tissue.
When and How to Introduce Light Activity
After the initial rest period, typically starting around Day 3 to Day 7, patients enter a transition phase where controlled, light activity is introduced. The goal during this stage is to prevent joint stiffness and promote healthy blood flow to the area without placing undue stress on the healing tissue. Activities are primarily non-weight-bearing or low-impact to safeguard the injection site.
Controlled movement may include gentle, active-assisted or passive range-of-motion exercises, which are often guided by a physical therapist. For lower-limb injections, short, slow walking may be permitted, but it should be limited to distances of five to ten minutes at a time and must be completely pain-free. Engaging in light activity helps to organize the new collagen fibers being laid down and prevents the formation of restrictive scar tissue.
This phase, which can extend through the second and third weeks, focuses on therapeutic movement rather than traditional exercise. Activities like stationary cycling or gentle swimming may be introduced if they do not cause discomfort and are approved by the treating physician. Resistance training and any activities involving impact, such as jogging or jumping, remain strictly prohibited to ensure the healing tissue is not overloaded or damaged.
Guidelines for Returning to Full Exercise
The return to a patient’s normal, strenuous exercise routine is a gradual process that typically begins around Week 4 and progresses over several months. Before resuming high-impact activities, medical clearance from the treating physician or physical therapist is necessary. Progression depends on meeting several criteria: pain-free movement, established stability in the joint or tendon, and measurable strength gains achieved through rehabilitation.
The principle of progressive loading is paramount during this phase, ensuring that the healing tissue adapts to stress gradually. Initially, activities like light cardio, such as elliptical or rowing, might be resumed at a significantly reduced intensity, perhaps 25% of the pre-injury level. This intensity is slowly increased over time, often in increments of 10% to 15% per week, provided there is no increase in pain or swelling.
For strength training, heavy weightlifting that directly stresses the injected area must be approached with caution and delayed until later in the recovery timeline, often after six to eight weeks. The focus should shift from high weight and low repetition to low weight and high repetition to build muscular endurance and protect the healing site. Rushing this gradual process can overload the partially regenerated tissue, potentially negating the benefits of the PRP injection and causing a setback in recovery.
Sport-specific training, which involves rapid movements, pivoting, or competitive stress, is usually the final activity to be reintroduced, often only after two to three months or more, depending on the injury. The progression involves moving from controlled, therapeutic exercises to functional movements and finally to full-intensity, sport-specific drills. Communication with a physical therapist is necessary to ensure the patient is progressing safely and the healed tissue can tolerate the increasing demands.