IMPACTS OF MUSCLE TRAINING LOADS ON COLLEGE STUDENTS' PHYSICAL FITNESS

ABSTRACT Introduction: Due to the excessive value of contemporary intellectual education, the physical fitness of college students has become precarious. This gradual deficit requires innovative solutions to inhibit the negative impacts on the physical quality that inevitably impact students' learning ability. Objective: Verify the impacts of varied loads in muscular strength exercise on college students and their practical repercussions on the diversified development of physical education classes. Methods: We selected 90 non-sporting college students, sedentary and without physical diseases, divided into experimental group 1 with medium intensity load, experimental group 2 with a low-intensity load, and a control group. Before and after the experiment, the relevant fitness indicators were evaluated, and finally, the data were statistically integrated and analyzed. Results: Group 1 increased from 52.25 ± 5.57kg before training to 54.56 ± 6.02kg, with a very significant change; experimental group 2 increased from 53.32 ± 4.89kg before training to 54.21 ± 5.22kg, showing a very significant change as well. Conclusion: Establishing the intensity of load muscle training scientifically and rationally can improve college students' physical quality and muscle strength, and promote the healthy and coordinated development of their psychological and physical quality. Level of evidence II; Therapeutic studies - investigation of treatment outcomes.


INTRODUCTION
Education is not only a simple knowledge learning, but also a part of education, which is the basis for professional learning. 1Without a healthy body and good spirit, it is difficult to carry out long-term mental work, and the learning effect can not be guaranteed.Compared with the physical quality education and healthy growth of college students, schools and families tend to pay more attention to students' test results and learning ability. 2 As a result, the physical function and health level of college students are declining year by year.The level of college students' physical ability is not only related to their own healthy growth, but also closely related to the future of the country and the nation. 3As the future of the country, it is very necessary and important for college students to exercise and strengthen their physical quality, especially the muscle strength training. 4When carrying out muscle strength training, the size of training load is related to the actual effect of muscle strength training under the consistent state of scientific and systematic training methods. 5In general, the training load is related to the weight of training equipment, the total training time, the rest time between groups, the number of repetitive training groups, and the training frequency. 6Only according to the different physical conditions of different subjects in training, according to scientific and systematic training methods, with reasonable and appropriate training load, specific muscle training is carried out for muscles that need to be strengthened, can the comprehensive and balanced development of body muscles be comprehensively improved, the body muscle content of college students be improved, and their healthy body and sound spirit be cultivated. 7

Research objects
Through searching and researching the existing authoritative literature, this paper summarizes the muscle strength level and development needs of adults.The study and all the participants were reviewed and approved by Ethics Committee of North University of China (NO.21N-THU-103CO).At the same time, according to this experiment, many training methods of load muscle training have been selected, which makes the research process of this paper more specific and the cognition of load muscle training more scientific.After the design of the specific experimental scheme, we used the methods of interview and questionnaire to carry out intellectual interaction with the professional scholars studying sports, experts in sports rehabilitation and muscle dynamics, and the current physical education teachers who are teaching at the university.We further refined, supplemented and improved the experimental scheme, and finally determined the experimental scheme.With the unanimous consent of the head teacher and guardians of the tested students, among the freshmen and sophomores of non sports majors, there are 90 college students who have no hypertension, cardiovascular disease, bone and joint disease, and have not undergone professional muscle strength training within one year, and they volunteer to participate in this load muscle training experiment.The 90 college students were equally divided into three groups: experiment group 1, experiment group 2 and control group.Their age, height and weight are shown in Table 1.

Research methods
The muscle load training experiment lasted for 8 weeks, twice a week.The experimental group received muscle training.One group had 10 consecutive repetitive movements.The rest time between the groups was 1-2 minutes according to individual differences.A total of 15 groups were trained.The three groups were a large group, and the rest time between the large groups was 5 minutes.In order to reduce the influence of irrelevant factors on the accuracy of the experiment, during the experiment of muscle load training, each subject's daily diet structure, eating time and work and rest rules were consistent.Before and after the experiment, the subjects carried out body composition indicators, ultrasonic testing and muscle electrical signal measurement respectively.After the experiment, the data obtained were integrated and further analyzed.

Effects of muscle training with different loads on body muscles
After 8 weeks of weight bearing muscle training, the changes of students' upper limb muscle quality are shown in Table 2.
It can be seen from the data in Table 2 that, on the whole, the upper arm circumference of the two experimental groups changed significantly before and after training, P<0.01.The upper arm relaxation circumference and forearm circumference of the experimental group 1 had the The changes of three indexes in the control group were not significant.It is proved that the medium load muscle training has a significant impact on the upper limb, and the small load muscle training also has a certain impact on the upper limb muscle, but compared with the medium load muscle training, the impact is more significant.The data in Table 3 shows that after 8 weeks of training, the changes in calf circumference and thigh circumference of Group 1 with moderate load muscle training are relatively significant (P<0.05), in which the calf circumference increases from 37.57 ± 3.08cm to 38.15 ± 2.78, and the thigh circumference increases from 55.01 ± 3.77cm to 55.62 ± 3.28cm, indicating that moderate load muscle training has a significant impact on the growth of lower limb muscles and the changes in leg circumference.In contrast, the two groups of experiment with low load muscle training had no significant changes in two indicators, P>0.05, but the overall growth was slight.The circumference of the lower leg changed from 36.73 ± 2.25cm to 37.02 ± 2.16cm, and the circumference of the thigh changed from 56.02 ± 3.41cm to 56.39 ± 2.06cm.This shows that compared with moderate load muscle training, the impact of low load training on the lower limb muscles was weak, which is related to the training methods and training duration.There was no significant change in the control group (P>0.05).

Impact of load muscle training on cardiopulmonary function
The influence of different load muscle training on cardiopulmonary endurance is shown in Table 4.
Compared with the data before training, it can be seen from the results in Table 4 that the indexes of heart rate and vital capacity of Group 1 and Group 2 have relatively significant changes (P<0.05).The frequency of heart rate showed a certain downward trend.The frequency of heart rate in Group 1 decreased from 67.09 ± 8.59b/min before training to 62.51 ± 5.57b/min, and the frequency of heart rate in Group 2 decreased from 66.91 ± 7.16b/min before training to 62.03 ± 6.35b/ min.There was no significant change in the control group, but it also showed a downward trend, from 66.63 ± 6.61b/min before training to 64.12 ± 6.01b/min.Generally speaking, the heart function of athletes is strong, so the heart rate will be lower than that of ordinary people.After 8 weeks of regular exercise, the heart rate of the tested students also tends to be more gentle, indicating that moderate and low load muscle training can improve the heart function of students to a certain extent.At the same time, the vital capacity of the experimental group and the control group showed significant changes.The vital capacity of the experimental group 1 increased from 2.86 ± 0.83L before training to 3.25 ± 0.62L, the vital capacity of the experimental group 2 increased from 2.81 ± 0.49L before training to 3.11 ± 0.17L, and the vital capacity of the control group increased from 2.79 ± 0.52L before training to 2.95 ± 0.67L.

Effect of load muscle training on physical fitness
The change of body muscle will further affect the improvement of college students' physical quality.As shown in Table 5, the physical quality of the tested college students before and after the training shows a different degree of change.
As shown in Table 5, the weight, BMI, body fat rate and muscle mass of the students showed significant changes before and after participating in the load muscle training, of which the change of muscle mass was the most obvious, P<0.01.The experimental group 1 increased from 52.25 ± 22kg, the change is also very significant.At the same time, the change of muscle mass in the control group is small and shows a certain degree of reduction, which shows that the scientific muscles have a significant impact on improving the muscle mass of college students, while daily exercise has no obvious effect on the growth of muscle mass because of more aerobic exercise.

DISCUSSION
After eight weeks of training, the body composition structure of the three groups of subjects changed to varying degrees.After systematic and regular muscle training, the body mass index and body fat rate of the subjects decreased significantly.When the total amount of muscle increased, the muscle strength also increased.At the same time, after a long time of muscle load training, the muscle strength and cardiopulmonary function also improved.During the 8-week muscle load training, the muscles of the upper and lower limbs of the subjects were significantly improved by medium intensity large load, low intensity medium load and ordinary routine training.From the specific experimental data, the strength training of low intensity and medium load muscles in the experimental group 2 has a significant effect on the muscle strength of the college students, while the strength training of high intensity and large load muscles in the experimental group 1 has a more significant effect on the muscle strength of the college students.In addition, it can be seen from the data in Table 5 that both load muscle training and daily physical exercise have a certain effect on the reduction of students' body fat rate, in which the muscle training process has a very significant effect on the improvement of muscle mass, but the moderate load muscle training has no significant effect on weight reduction, while the low load muscle training has a significant effect on weight reduction.In contrast, daily sports activities have little effect on improving muscle mass, but they will still reduce body fat and students' weight to a large extent.Because muscle training includes aerobic and anaerobic exercise, it will burn fat first and then increase muscle content during training, so it has little impact on weight change.However, since the training lasts only eight weeks, small load muscle training and daily physical exercise are effectively burning fat, so the impact on weight is more obvious than heavy load muscle training.

Table 1 .
Basic information of the experimental group and the control group.

Table 2 .
Changes of upper limbs of students before and after training.

Table 3 .
Changes of lower limbs of students before and after training.

Table 4 .
Changes of students' cardiopulmonary function before and after training.

Table 5 .
Changes of students' physical quality before and after training.