Aim: The aim of the study was to examine and compare the time-dependent effects of IASTM and FR applications on delayed muscle pain and physical performance.

Method: 50 physically active healthy male individuals between the ages of 20-35 will be included in the study. Participants will be divided into 3 separate groups as instrument assisted soft tissue mobilization(IASTM), foam roller (FR) and control group. DOMS creation protocol will be implemented after preliminary evaluation. IASTM and FR groups will be treated after the formation of doms. The control group will not be applied. participants are evaluated 1 day before the doms were created and at 24, 48 and 72 hours after doms created. Subjetcs were tested for physical activity level with IPAQ-SF, flexibility with sit and reach test, pain with Visual analog scale, edema with thigh circumference measurement, explosive power with horizontal and vertical jump test, dynamic balance with y balance test and isokinetic muscle strength of the quadriceps and hamstring muscles with isokinetic dynamometer.

Muscle soreness after exercise is often referred to as delayed onset muscle soreness (DOMS). DOMS is common in people who do strenuous and unusual exercise and physical activity. DOMS, also called Grade 1 muscle strain, is characterized by localized tenderness and pain. DOMS typically peaks between 24-72 hours after strenuous exercise and disappears within 5-7 days.2-4 Associated with exercises involving eccentric muscle movement DOMS also affects athletic performance by causing decreased range of motion and reduced peak torque.

According to literature, many improvement strategies have been used by athletes, coaches and health professionals to minimize DOMS symptoms and improve performance. These strategies include massage, stretching exercises and the use of anti-inflammatory drugs. Studies conducted in different populations to date show that the results of these treatments on DOMS usually have minimal analgesic effects. Improvements in strength and flexibility have also been observed in some studies.

Myofascial release method, developed by James Cyriax, Instrument assisted soft tissue mobilization (IASTM) is applied with specially designed instruments. In particular, the use of instruments in the technique, which has been shown to have a mobilizing effect on soft tissue to reduce pain, increase range of motion and function, creates a deeper effect and allows specific treatment. It is also known to provide a mechanical advantage for the clinician by reducing the pressure on the hand. Current studies show that IASTM can improve joint ROM change the perception of pain and increase local circulation

Foam Roller (FR), another method used for myofascial relaxation, is a method that has been frequently researched in recent years, especially in the warming and recovery phases. FR includes a wide variety of therapy techniques, including massage and self-massage. Myofascial release is used to treat somatic dysfunction causing pain and limitation. Self myofascial release is performed using FR or stick. To demonstrate the effect of self-myofascial relaxation, studies focused on the effect of FR on increasing ROM, reducing muscle soreness, and lower extremity biomechanical performance. The first effect is associated with recovery and recovery, while the second effect is associated with performance. There are several studies reporting that FR also has a major impact on improving flexibility. In fact, there are studies reporting that it shows this effect even after a single FR session.

The number of studies investigating or comparing the effects of FR and IASTM techniques on delayed muscle pain is very limited in the literature. Studies comparing the effects of the two techniques have generally compared their effectiveness in the upper extremity muscles. In the lower extremity, there is only one study investigating and comparing the effects of both treatment methods in healthy active individuals. In this study, only the effects of techniques on flexibility were evaluated. Therefore, the aim of our study is to examine and compare the time-dependent effects of IASTM and FR applications on delayed muscle pain and physical performance.

Method:

Participants who want to take part in the study will first be informed about the study in written and verbal form and their written consent will be obtained. Then, the socio-demographic characteristics and information of all participants will be recorded. On the same day, the assessments detailed below will be audited by all participants and they will be given the opportunity to practice in order to adapt to the assessment methods. Preliminary evaluations of all participants (all evaluations mentioned in the evaluations section) will be taken at least 48 hours after the practice day. After the preliminary evaluations, individuals will be randomly divided into 3 groups with GraphPad - version 8.4.3 software in order to determine which group (foam roller/instrument assisted soft tissue mobilization or control group) the participants will be in. Treatment methods to be applied to the groups were divided into two as IASTM and Foam roller.

Group 1 (Foam Roller): It will be applied to the Quadriceps, Hamstring and Gastrocnemius muscles of the participant's dominant lower extremity using a rigid FR. A total of 6 minutes will be applied to a person, 2 minutes for each muscle. Pressure intensity; According to the Visual Analogue Scale, which is the point where pain will not be felt but moderate to severe discomfort will be felt, it will be done at a severity of 7/10.

Group 2 (IASTM): Myofascial release technique will be applied to the Quadriceps, Hamstring and Gastrocnemius muscles in the dominant lower extremity of the participant with the Graston technique®, the instrument to be used in this technique. The application will be at 45° angles for each muscle, 2 minutes, for a total of 6 minutes. The IASTM application will include sweep-fan-sweep strokes and cycles will be performed along each muscle for a specified time.

Group 3 (control): Individuals in this group will be asked not to participate in any physical activity during the evaluations (5 days) and to do their normal daily activities

Method: After the first evaluations, DOMS will be applied 48 hours later. Immediately after the DOMS is created, FR will be applied to those in Group 1, IASTM will be applied to those in Group 2, and no application will be made to those in Group 3. On the same day, 30 minutes after the applications, pain (VAS) and edema (Quadriceps circumference measurement) will be evaluated. At 24, 48 and 72 hours, all evaluations will be repeated to the participants.

DOMS creation protocol: It will be created by eccentric contraction in the isokinetic device. The patient will be positioned with the knee at 90° flexion. Then, the knee extensors will be asked to perform 5 sets of 15 repetitions of maximal voluntary eccentric contraction at an angular speed of 60°/s. There will be 2 minutes of rest between sets.

Inclusion Criteria:

• Recreationally active (who do moderate-vigorous physical activity at least 2 times a week)
• Those who are moderately and/or highly active according to the IPAQ scale
• Between the ages of 20-35
• Doing moderate to severe physical activity at least 2 times a week
• Those who have not received IASTM or Foam Roller application in the last 30 days

Exclusion Criteria:

• Those who are allergic to the intermediate used material in IASTM application
• Those who use alcohol and supplements
• Those who have any lower extremity injury in the last 6 months
• Those with orthopedic or neurological disease