EFFECTS OF HIGH-INTENSITY TRAINING ON BASKETBALL PLAYERS

ABSTRACT Introduction: Basketball represents much more than a high-intensity exercise. Like most ball games, it is a continuous movement system. Objective: Study the effect of high-intensity interval training (HIT) on the aerobic metabolism of young basketball players. Methods: The author randomly divided male basketball players into an upper limb HIT group, lower limb HIT group, and control group by experimental method and statistical analysis, the control group received routine training, and aerobic exercise capacity was measured by increasing load test before and after the experiment. Results: During the lower extremity experiment, the mean power (MP) and peak power (PP) of the 4th full-force pedal stroke in the lower extremity HIT group increased (P<0.05), and the T/C ratio of the lower extremity HIT group was also implemented (P<0.05). There was no significant change in the indices of the control group (P>0.05). Conclusion: Upper extremity HIT in young male basketball players improved only upper extremity aerobic exercise capacity. In contrast, lower-extremity HIT improved both upper-extremity aerobic exercise capacity and lower-extremity anaerobic exercise capacity. Level of evidence II; Therapeutic studies - investigating treatment outcomes.


INTRODUCTION
Basketball is a form of high-intensity interspersed with low-intensity exercise, like most ball games, it is an intermittent movement pattern, with short (≤6 seconds) secondary or high-intensity efforts, interspersed with it, it consists of a recovery period of intense (≤60 s) moderate to low-intensity effort. 1 The performance requirements of basketball include aerobic and anaerobic metabolism, of which anaerobic metabolism is considered to be the main energy system.If the recovery period is relatively brief and remains elevated until the next sprint, aerobic metabolism will be used instead to generate adenosine triphosphate. 2igh-intensity movements, such as rapid changes in direction, speed, and repetitive jumps, are considered key elements of successful performance in basketball games. 3igh-intensity interval training is a training method that can improve anaerobic and aerobic capacity at the same time, high-intensity interval training can increase the activity of glycolysis and oxidative enzymes at the same time, enhancement of short-duration high-intensity exercise performance and VO2 max, the reason for these adaptations is that the intermittent approach reduces the contribution of anaerobic metabolism to ATP production, improves the contribution of aerobic metabolism to energy production, interspersed with recovery periods between high-intensity exercise periods, the aerobic metabolic pathway promotes the oxidation of lactate and the resynthesis of creatine phosphate, thereby enhancing the ability of the aerobic energy metabolism system. 4For basketball players, the help of aerobic capacity to maintain performance in the late game, as well as the speed and vertical jump in power are quite important to the game, and HIT is considered to be a kind of efficiency, it can improve the training methods of aerobic and anaerobic energy metabolism at the same time; Studies have shown that high-intensity interval training can increase endurance exercise performance, muscle capacity, fat oxidation rate, aerobic capacity and anaerobic threshold, etc.; The uphill running is a training method that can increase the load on the lower limbs.Therefore, the author discusses the combination of high-intensity interval training and uphill running to improve the aerobic capacity of basketball players, at the same time, it can improve the power of the lower limbs.Therefore, high-intensity interval training uphill is a beneficial training method for coaches and athletes. 5Taylor J L et al asked wrestlers to perform 4 weeks of HIT (35m full sprint, 10s interval, 2 times/week) after VO2max (5.4%) and the peak power (36.5%) and average power (9.4%) during the experiment.1%) were significantly improved, serum creatine kinase (CK) at rest increased by 20.3%, suggesting that HIT-induced muscle damage occurred; In addition, the peak lactate concentration and testosterone/cortisol ratio increased after the experiment, indicating that endocrine and metabolic functions were improved. 6Sarlis V et al. performed ultra-high-intensity HIT programs for wrestlers and karate respectively, and found that VO2max increased by 4.6% and 5.4%, respectively, during the lower extremity incremental load test. 7A study by Zambrano M C and others reported that after 4 weeks of HIT, the ventilatory threshold of cyclists in the lower extremity incremental load test increased by about 16% to 24%, which was basically consistent with the increase in PLT (17.5%) in the study. 8ecause the upper body (dribbling, confrontation) and lower body (explosive power, agility) need to cooperate in basketball games, athletes often use power bicycles to develop cardiopulmonary ability, upper and lower body strength and explosive power during training, however, little attention has been paid to whether the HIT effect is site-specific, and in-depth research on this has guiding significance for pre-competition scientific training. 9The purpose of this study was to investigate the effects of different parts of HIT (upper extremity HIT, lower extremity HIT) on aerobic and anaerobic exercise capacity, physiological adaptation and muscle damage of basketball players.It is speculated that the incorporation of HIT into routine training can further improve the athletic ability of athletes, and the training effects of different HIT programs are site-specific.

METHOD Research object
Forty-five male basketball players from a sports school (athletic level 1, 17-30 years old) voluntarily participated in this experiment, and signed informed consent before the experiment.The subjects were healthy, without various acute or chronic diseases, and had no recent medication history.The training plan for each athlete is basically the same, that is, weekly training 5-6d, special training 2-3h/d, 4 times/week, and strength training 3 times/week.The subjects were randomly divided into upper extremity HIT group, lower extremity HIT group and control group, 15 people in each group; The control group received routine training, while the upper limb HIT group and the lower limb HIT group received 4-week upper limb or lower limb HIT program training on the basis of routine training, respectively.The general characteristics of the subjects are shown in Table 1, there were no significant differences in baseline variables such as age, height, body mass, body mass index, body fat percentage and training years before the experiment among the three groups (P>0.05).

Experimental Design
Subjects performed a total of 9 tests and 4 weeks of training.1st time: Familiarize yourself with the laboratory environment and test procedures and perform the measurement of body morphological indicators (height, body mass, body mass index, body fat percentage).
The 2nd time: Perform an upper body power cycling incremental load experiment, record VO2max, maximum aerobic power (maximalaerobicpower, MAP), maximum heart rate (maximum heart rate, HRmax) and lactic acid threshold (LT) power (PLT) and oxygen uptake volume (VO2LT).
The 3rd time: A lower limb power cycling incremental load experiment was performed, and VO2max, MAP, HRmax, PLT and VO2LT were recorded respectively.
The 4th time: An upper limb Wingate experiment was performed to record the peak power (peakpower, PP), mean power (meanpower, MP) and total work (totalwork, TW).
The fifth time: A lower limb Wingate experiment was performed.In addition to recording PP, MP and TW, venous blood was taken at rest and after the Wingate experiment to measure muscle injury markers and blood lactic acid (Bla).The above adjacent tests are at least 1d apart and completed within 2 weeks.The subjects were then trained for 4 weeks, and the 6th to 9th tests were performed 48 hours after the last training, and the test contents corresponded to the above 2nd to 5th tests respectively.All tests were performed between 7:00-9:00 am to reduce the influence of biological rhythms, and the test order was random.

Statistical processing
All data are expressed as "mean ± standard deviation".SPSS 20.0 was used for statistical processing of data, paired t-test was used for   intra-group comparison before and after the experiment, one-way analysis of variance was used for inter-group comparison, and timecourse changes in blood lactate and anaerobic exercise capacity were analyzed by repeated measures. 10

Figure 1 .
Figure 1.Changes of TW during the lower limb Wingate experiment.

Figure 1 .
Figure 1.Changes of MP during the lower limb Wingate experiment.

Table 1 .
General characteristics of subjects.