1. Introduction
tress fracture, compartment syndrome, and medial tibial stress syndrome are the three most common forms of injuries caused by overexertion or exercise leg-pain, among which medial tibial stress syndrome is more common than other cases [1]. Medial tibial stress syndrome is one of the few common injuries caused by the lower leg’s overexertion, known as exercise leg-pain or shin splint. This study suggests that people with medial tibial stress syndrome may have excessive plantar pressure in different parts of the ankle, which must be scrutinized. 
Increased pressure on the feet sole in the long-run has severe consequences, including increased pain in the sole, increased fatigue, and withdrawal from activities and competitions. It may also increase treatment costs and lead to chronic side effects. On the other hand, there is a research gap in studying the impact of medial tibial stress syndrome on female athletes’ level of plantar pressure. Therefore, in this study, the researcher intended to evaluate plantar pressure in people with medial tibial stress syndrome.
2. Materials and Methods
This applied research was conducted through a quasi-experimental method with a comparative design. The statistical population of this study consisted of all female athletes in the field of physical education. This study’s statistical sample included 70 female athletes in Tehran city (35 subjects with medial tibial stress syndrome and 35 healthy individuals). At first, the subjects’ height and weight were measured by a height gauge and a digital scale. A foot scan device (made in Finland) with a sampling rate of 300 Hz was used to record the plantar pressure variables. This device has a pressure measuring plate with dimensions of 50 x 40 cm and 4096 sensors, connects to the computer via cable and SB, and collects data at a frequency of 300 Hz [14]. 
Each individual’s plantar pressure was extracted separately in ten different areas in the sole (including first finger, second to fifth fingers, 1st to 5th metatarsals, the middle part of the foot, inner ankle, and outer ankle) by the foot scanner output. In the descriptive statistics section, the Mean±SD of the plantar pressure in the ten areas was presented. In the descriptive statistics section, the plantar pressure in both groups was determined using an independent t-test at a significant level of P≤0.05.
3. Results
The results of this study indicated that the plantar pressure distribution in the group with medial tibial stress syndrome in 6 variables of the “1st finger”, “1st metatarsal”, “2nd metatarsal”, “3rd metatarsal”, “middle part of the foot”, and “inner ankle” was higher than the control group (P≤0.05). But the other measured variables of plantar pressure, including the “2nd to 5th fingers”, “4th metatarsal”, “5th metatarsal”, and “outer ankle”, were not significant in both groups (P≥0.05).
4. Discussion and Conclusion
Since the amount of plantar pressure in the inner part of the sole (including the “1st finger” and the “1st to 3rd metatarsals”) as well as in the “inner ankle” was higher than the control group, this could be due to excessive foot pronation in people with medial tibial stress syndrome during the stress phase of the walking cycle. Simultaneously, the amount of pronation increased the amount of muscle strain on the anterior tibialis tendons, posterior tibialis, flexor hallucis longus muscle, and flexor digitorum longus muscle. This is because the increased ankle pronation leads to an increase in the length of the anterior leg muscles and a shortening of the posterior leg muscles for a long time (in foot pronation abnormalities, the anterior leg muscles are in a position of increasing length and the posterior leg muscles are shortening due to reduced length) (Table 1).


Increasing the rate of muscle strain in these tendons can be an important risk factor for the occurrence of medial tibial stress syndrome and increasing the.
rate of plantar pressure [3, 12]. The increase in plantar pressure may be due to biomechanical differences between participants with a history of medial tibial stress syndrome compared to the control group.

Ethical Considerations
Compliance with ethical guidelines
All ethical principles are considered in this article. The participants were informed of the purpose of the research and its implementation stages. They were also assured about the confidentiality of their information and were free to leave the study whenever they wished, and if desired, the research results would be available to them.

Funding
This research did not receive any grant from funding agencies in the public, commercial, or non-profit sectors. 

Authors' contributions
All authors contributed equally to the writing of the article.

Conflicts of interest
There was no ethical considerations to be considered in this research.
 

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