Comparison of the Effect of Eight Weeks of Traditional Resistance Training and TRX on Muscle Injury Indices of Inactive Women

Intense physical activity, despite its various benefits for general health, can cause possible damage to various tissues of the body due to increasing oxidative stress through increasing production of reactive species. Muscle bruising and pain is a common experience that occurs after performing unusual and intense activities, especially after resistance and extroverted activities. Delayed muscle spasm is associated with the release of creatine kinase, lactate dehydrogenase, and aspartate aminotransferase, and can be measured by the release of these enzymes into the blood. Numerous studies have examined the effect of resistance trainings on muscle injury indices that creatine kinase and lactate dehydrogenase, spartate aminotransferase, alanine aminotransferase and myoglobin indices increased significantly after exercise. In another study, they did not see any significant changes in CK and LDH muscle injury indices after 3 hours of cycling. Therefore, due to the injuries, researchers have drawn attention to the effects of resistance exercise on muscle injury indices. Although resistance training improves performance, it does not prevent the release of inflammatory and traumatic factors, so these factors can cause acute sports injuries, which will be especially important at a young age. Nowadays, special attention is paid to the use of various methods of resistance training, the most prominent of which is TRX or the same resistance training exercises suspended by body weight. Therefore, considering the different effects of sports activities, especially strength training on different parts of the body and the possibility of injury in these exercises, and considering the differences in the type of resistance training programs such as TRX and circular resistance, it is important to pay attention to the effects of this type of training and muscle injury indices. Also due to the contradictory results about the effect of exercise, especially the effect of resistance activity on muscle injury indices and also the lack of sufficient research on the long-term effect of TRX training on muscle injury indices and especially insufficient research on the comparison of resistance training and TRX, the researcher decided to compare 8 weeks of traditional resistance training and TRX on the indicators of muscle injury in inactive women.

In this semi-experimental study, (28) healthy inactive girls with a mean age of 21.00 38 1.38 years were randomly divided into three groups: traditional resistance training (9), TRX training (9) and control (10). The experimental groups performed the training protocol three times a week for 8 weeks with an intensity of 65 to 80%. Blood samples were taken before training and 48 hours after the last training session and creatine kinase and lactate dehydrogenase levels were measured. Data were statistically analyzed using Shapiro-Wilk, dependent t-test and one-way analysis of variance.

The results showed that traditional resistance training and TRX both cause significant changes in LDH levels, while there was no significant difference in CPK variable from pre-test to post-test in all three groups. Also, in examining the differences between groups, no significant difference was observed between the three study groups at CPK levels. While there was a significant difference in the amount of lactate dehydrogenase between the three groups (p <0.05). According to the results of Table 3, there was a significant difference in the levels of lactate dehydrogenase between the resistance group and the TRX group (p = 0.0001), the control group with the TRX group (p = 0.0001) and the control group with the resistance group (p = 0.012) was observed.

The presence of CK and LDH in the blood is an indirect sign of muscle damage as well as the diagnosis of medical conditions such as heart attack, muscular dystrophy and brain diseases. Cellular disorders, especially muscle cells, can cause CK and LDH to leak from cells into the blood serum. The findings of the present study showed that although there was a difference in the means of the three groups in both variables of creatine kinase and LDH, but this difference was significant only for LDH (P <0.05). The results of this study also showed that there is no significant difference in creatine kinase index between the two types of traditional resistance training and TRX after eight weeks. These factors affect the amount of response and the time period of secretion along with the injury. In general, the researchers state that intense resistance activities due to increased mechanical-metabolic pressure on the fibers lead to rupture of fibers, fluidization of z-plates, rupture of sarcolemma, displacement of intracellular organs, instability of plasma membranes and increasing secretion of intracellular proteins, after performing the resistant and intense activity. In fact, fatigue of muscle fibers following exhaustive activities can lead to increasing permeability of cell membranes to intracellular free calcium ions and dysfunction of sodium-potassium pumps, causing instability of cell membranes and activation of proteases and intracellular lipases. There is a close relationship between the release of phospholipases and creatine kinase due to the activity of intracellular proteolytic enzymes stimulated by calcium in the isolated muscle of mammals. The results of this study on LDH showed that the LDH of the experimental groups was significantly lower than the control group. Lactate dehydrogenase is one of the enzymes involved in the anaerobic pathway of ATP production. The secretion of lactate from the training muscle and the activity of the muscle pump indicate the role of continuous exercise training on the rate of cell damages. It has also been shown that trained people have less enzymatic release into the bloodstream than people who did not, which may be due to the adaptation of trained people to the physical activity and exercise; because the skeletal muscles of athletes and trained people have the highest amount of ATP, which is used during exercise and physical activity to maintain the integrity of the cell membrane, and as a result, reduces the leakage of enzymes into the blood. In any case, it seems that as a result of running consecutive weeks of regular exercise programs, intramuscular adaptation may be established, and the nature of resistance training programs causes adaptation to occur at all levels, including intramuscular and better blood supply, which reduces the activity level of CK and LDH enzymes as indicators of muscle and cell damage; therefore, it seems that the use of appropriate methods of training reduces the disruption of biochemical changes. Therefore, according to the findings of the present study, it can be stated that the implementation of TRX training program and traditional resistance both can significantly reduce the rate of LDH cell damage index and no change in CK, and there is no difference between this type of training on the indicators muscle damage in young women, so both types of exercise can have beneficial effects on muscle injury indices.