Ruidong Liu
Department of Physical Education, Tsinghua University, China
In order to find the impact of the two methods on functional movement screen and Physical Performance, Core and traditional resistance strength training was applied to the subjects for 8 weeks, so as to provide a theoretical basis for core and traditional resistance strength training.
Selected 40 male college students in general as research subjects. The experimental group was conducted for a period of 8 weeks of core strength training and the control group was conducted traditional anti-resistance training for 8 weeks. Before and after the training, FMS and Physical Performance had been tested. Data were subjected to SPSS ANOVA for repeated measurements. When the main analysis indicated a significant interaction (P< .05) between factors, follow-up analyses were performed, adjusting error rates according to Bonferroni.
(1) The core strength training for 8 weeks could significantly enhance the quality of college students' functional movement screen ( FMS ), but compared with the traditional strength training, no significant different on the improvement of FMS test results ( P > 0.05 ); (2)The core strength training could significantly enhance the ability of speed , coordination and flexibility of college students ( P < 0.05 ) compared with the traditional strength training, but its effect on the lower limb's jumping ability was far less than the traditional strength training, jumping ability was still need to be improved by high intense resistance training.
Core strength training cannot replace the traditional resistance strength training for improving
the muscle strength, explosive power and the ability of balance. Therefore, in the later training of
strength, we should distinguish the different influence between traditional resistance training and
core strength training for physical performance.
Kangkang Zhou
Physical Training and Rehabilitation Center at National Sports Trainging Center, China
To determine the relationship between the top Chinese table tennis athletes' score on the FMS and the likelihood of injury risk.
This research mainly use literature method and the test method to do the FMS test for the Chinese junior national man and woman table tennis athletes and the national top youth athletes total 81 players before the start of the season. After about six months monitoring injury in the season,by using the ROC curve graph and discrimination formula to predict injury.
The FMS mean score for the 81athletes was 13.4±1.5 points.male was 13.2±1.5 points Female was 13.5±1.5.There was no significant difference between male and female players (P=0.347).The top Chinese table tennis athletes who get the score(<12.5)suffering a potential injury risk probability is about 28.5 times greater than the score of (>12.5) points.( with specificity of 0.886 and sensitivity of 0.811. The odds ratio was 28.5).Discriminant analysis screened out four tests closely with injury risk of the top Chinese table tennis athletes: deep squatRotary Stability hurdle step, active straight leg raise.
The results of this study can be concluded that: the 7 tests in the FMS test are not applicable to all sports and all the people. The significance of each test in different sports items and different groups may be different. Discriminant formula and the injury risk threshold can be used to complement each other. As a common method to determine the potential injury risk.
Ming Yang
Tsinghua University, China
This study is conducted to discuss the application of High-Intensity Interval Training (HIIT) in Pre-Contest Preparation of Bodybuilders, whether it's suited in the caloric deficit condition to help the athletes lose body fat while maintaining the lean body mass at the same time.
We reviewed the relative literatures on the application of HIIT with different populations and interviewed the bodybuilders with different training levels. expert interviews were also used in the study.
A comparison among HIIT, LIT and other fat losing programs from the aspects of muscle fiber recruitment, stimulation of hormone production, fat loss and the feasibility of HIIT is also made in the study.
First of all, HIIT recruits more types of muscle fibers to excute exercises, especially the fast-twitch fibers, there are still debates about if it's benifitial under the circumstance of strictly restricted intake of total calorie and carbohydrates.
Secondly, Physical activities affect the endocrinium system, HIIT stimulates the production of adrenaline, norepinephrine, thyroid hormones and GH. Theoretically, this helps with gaining/maintaining lean body mass and losing body fat. In addition, high intensity exercises stimulate the secretion of leptin, which reduces the appetite of athletes.
Thirdly, during the pre-contest preparation, especially the last weeks leading to the show, the total caloric intake and carbohydrate intake are extremely low, the competitor gets more time to recovery by doing HIIT.
(1)HIIT is of great benefit to enhance the health and performance for bodybuilders before a competation.
(2)It's recommended that athletes and the general public who need to lower their body fat percentage rapidly and enhance health and performance may use HIIT in their training routine.
(3)The human body is extremely complicated and everyone reacts differently to the stimulation, it's important to adjust the training protocol according to the training level and the period of the time of the preparation.
Xudan Cai
Faculty of Physical Education, Ningbo University, China
The International Hockey Federation (IHF) introduced new rules governing field hockey matches (Here on in referred to as hockey) from 2015. It is thus plausible to think that these modifications may change the match specific physiological demands on the players. Therefore, the purpose of this study was to investigate the physiological demands of hockey matches under the new rules. To the authors knowledge this is the first study looking at the demands of competition after the introduction of the new IHF rules.
Four matches analyzing 16 elite Chinese field hockey players (Height:178 ± 4.41cm:, Weight:76.50 ± 6.12kg ) were record by using global positioning system (SPI Elite, GPS ports, Australia) and analyzed using Team AMS (v2014.11) software during 2015 Chinese National Tournament. Multiple paired t-tests were used to compare data between different positions and different quarters. Significance was set at P < 0.05. Average values were used to compare differences between new rules' and old rules' hockey matches.
The mean total distance covered by each player was 5788±1710m, and overall mean playing time was 37.8 ± 14.0min. Compared with other positions, strikers had a significantly greater high-intensity activity (>14km/h) percentage (strikers: 29.7±4.8%; midfielders:25.6±5.8%; defenders: 17.9±3.3%; P<0.01). Average sprint (defined as speed >19km/h, interval of at least 1 second) counts for each player was 25.5±9.9 per match, with an average duration of 2.5±0.3s. About 75% of sprint distances were between 5-20m, with recovery times varying greatly, however the two most frequently observed recovery times were >120s (36%) and 0-40s (35%).
These results suggest that the total distance and average playing time of field hockey players deceased, but the average intensity and percentage of high speed running distance significant improved in the new IHF rules' matches. The physical demands of different positions still have big difference. The strikers covered less total distance and shorter playing time, but performed the highest average speed and percentage of high speed running distance than other positions in the new IHF rules' field hockey matches. However, our research was limited to only 4 matches, and further research should be conducted to confirm these findings during "new rule" hockey tournaments.
Tienan Wu
Heihe University, China
The aim of this study was to find the best way of recovery after intensity training for elite young swimmers in altitude training, providing theoretical basis for young swimmers' recovery in altitude training.
32 young elite male swimmers were recruited as subjects in this study, which sports grades were all above level-1. Athletes were randomly divided into 4 groups of 8 people each, including stretch (ST) and three different intensities of active recovery (AR30/AR50/AR70, an intensity corresponding to the speed of 30% · 50% · 70% of their best time of 1000m freestyle for 15min). The training period was 3.5 weeks on-altitude (1890m), blood lactate and heart rate were detected after the intensity training class and 15 minutes' later that arranged in the third week.
1. Compared with the TR group, blood lactate was lower in the group of AR30, AR50 and AR70 at the time after recovery exercise(p<0.05, respectively) significantly, heart rate was higher (p<0.05, respectively) significantly.
2. Compared with the AR70 group, blood lactate was lower at AR30 and AR50 at the time after recovery exercise (p<0.05, respectively) significantly, no significant between AR30 and AR50.
3. Compared with the TR group, blood lactate was lower in the group of AR30, AR50 and AR70 at the time 15 minutes' later (p<0.05, respectively) significantly, no significant in heart rate.
4. Compared with the AR70 group, blood lactate was lower at AR30 and AR50 at the time 15 minutes' later (p<0.05, respectively) significantly, no significant between AR30 and AR50. 5. Blood lactic acid decline rate is significantly higher in AR50 than the other groups (p<0.05) in the process of 15 minutes' recovery.
1. All these 3 active recovery methods in the water are better than the method of stretch on land after intensity training in eliminating blood lactated.
2. The intensity corresponding to the speed of 30% and 50% of the best time of 1000m freestyle for 15min are effective after intensive training.
3. The intensity corresponding to the speed of 50% of the best time of 1000m freestyle for 15min is recommend because of the lactate clearance.
Jiabin Yu
Research academy of Grand Health, Ningbo University, Ningbo, China
The purpose of this study is to investigate the differences in biomechanical parameters and neuromuscular control during the acceleration and maximum velocity phases of full-effort sprinting, and further to discuss the muscle function during the two phases. It was hoped that the information gathered here would provide insights into the physical characteristics required of a successful athlete, and training programs that would foster these characteristics.
VICON motion analysis system (200Hz, 12 cameras), KISTLER force plates (1000Hz, 3 force plates) and DELSYS wireless system (4000Hz, 7 sensors) were used to collect the kinematic, ground reaction force and EMG data of 20 sprint athletes during the acceleration and maximum velocity phase. The starting line was 12 meter and 40 meter from the first force plate for acceleration phase and maximum velocity phase, respectively. The cut-off frequency of low-pass filter was 12 Hz and 72 Hz for kinematic and ground reaction force, respectively. Intersegmental dynamics analysis during one stride was performed using a custom-written program prepared by C#. EMG data were filtered and rectified in DELSYS software firstly, and then inputted into a custom-written program prepared by C# to compute root mean square (RMS) in various periods. Paired-sample t-tests were used to determine differences in kinematic, kinetic and EMG variables between the acceleration and maximum velocity phases.
At the stance stage, the peak vertical force, knee extension muscle torque (MUS) peak and ankle plantarflexion MUS peak occurred at 30-40% of stance stage, and were greater during the maximum velocity than acceleration phase. The RMS of medial head of gastrocnemius during the stance stage was significantly greater during the maximum velocity than acceleration phase. At the swing stage, hip flexion MUS peak at the forward swing stage and hip extension MUS peak at the backward swing stage were greater during the maximum velocity than acceleration phase. The RMS of rectus femoris at the forward swing stage and biceps femoris were greater during the maximum velocity than acceleration phase.
At stance stage of the maximum velocity phase, the activation of gastrocnemius was greater to counter stronger landing impact caused by larger vertical force peak. At forward swing stage of the maximum velocity phase, the greater activation of rectus femoris produced greater hip flexion MUS to counteract greater hip extension inertial torque (INT). At backward swing stage of the maximum velocity phase, the greater activation of biceps femoris produced greater hip extension MUS to counteract greater hip flexion INT. All these findings had guiding meaning for sprint running training.
Haining Teng
Tsinghua University, China
The Chinese middle and long distance runner Teng Haining was the only yellow man in the men's 800 m final in 17th Incheon Asian Games and he, eventually, won the silver medal. This means that the yellow race also have a place in the men's 800m in major international sports competitions. In addition, 5 months before Incheon Asian Games, Teng had broken the national record of men's 800 m which lasted for more than 20 years in the IAAF (International Association of Athletics Federations) Challenge Race in Beijing. So I choose Teng as the subject and focus on his speed quality in the rear distance. Through analyzing his "lactic acid resistant—high speed" training technique to summarize the methods of improving 800m runners' speed quality.
(1) Survey Method; (2) Literature Search Method; (3) Interview Method; (4) Experimental Method.
It is generally accepted that 800m is the sport that require the combination of aerobic and anaerobic supplement. And the glycolysis supply energy system is the main energy supply system which is up to 80 percent and more, as a result, the immediate product of glycolysis supply energy ---- blood lactic acid will accumulate rapidly in body. So the speed after a large number of lactic acid accumulation decides directly the outcome of the competition. We conducted a HIIT(high-intensity interval training) experiment on Teng in an intense class. The requirement of this HIIT experiment is: the heart rate during running exercise is no less than 160 times/min ,the maximum heart rate percentage (HRmax%) is more than 80%, the interval is controled in 4 minutes, a total of 6 times 1000m running. In the "1000m 6"HITT experiment, Teng's actual HRmax is 167 times/min (HRmax% is 84%), the average heart rate of the interval between 1000m and 1000m can recover to above 84 times/min (HRmax% is 42%). The 1000m average result is about 3 minutes, the longest is 3'09'', the shorter is 2'54''. And after "1000m 6"HITT experiment, Teng's RPE( Rating of Perceived Exertion) is 15,which means tired but not very tired. It shows that Teng Haining has an excellent recovery ability in a short time. And 4 minutes latter, Teng runs a 1000m with all his forces and the result is 2'22'', RPE is 19(exhausted), HRmax is 195. We can see that after a high lactic acid accumulation training, Teng can also maintain a high speed to finish one more 1000m and get a well qualified result. We name this ability of him is "lactic acid resistant—high speed" pattern.
Teng Haining's exclusive "lactic acid resistant—high speed" pattern means that he can also obtain a strong sprint ability after a high accumulation of lactic acid. And HIIT training can improve his lactic acid resistant ability and sprint speed.
Yi Peng
Beijing Sport University, China
In swimming events, land training supplements and regulates water training; strength training is an effective means of sports injury prevention and performance improvement. Lactate tolerance training on land is able to enhance training levels and competition results of swimming athletes who participate in the short-distance swimming competition, improving stroke efficiency. Muscle strength is directly correlated to one's lactate tolerance ability, so we achieve the goal of improving the performance of short-distance events by designing and experimenting the lactate tolerance method of the combination of bench press and pushups according to the energy metabolism characteristics of short-distance events.
Experimentation and mathematical statistics
We chose 10 athletes, and assigned them randomly to two groups, namely the control group of weight increasing + RM decreasing and the experimental group of weight decreasing + RM increasing + pushups. We also chose blood lactate acid, RPE score and heart rate as test metrics, and found that the value of lactic acid showed a gradually increasing tendency in both the control group and the experimental group. The five average values of the tested lactic acid were: 3.206/3.926mmo/L;4.298/6.32mmo/L; 5.62/8.272mmo/L; 6.048/10.28mmo/L; 7.418/10.15mmo/L. According to five heart rate tests and RPE scores, the values of blood lactic acid, heart rate and RPE in the experimental group were higher than those in the control group. Training in the experimental group was more stimulating and intensive, and it achieved a better lactate tolerance effect.
The composite training of weight decreasing + RM increasing + pushups encourages blood lactic acid creation effectively. What's more, its heart rate and fatigue degree are close to what they are in real competition, and it has a favorable training effect.
Junjiro Kubo
Heisei International University, Japan
Judo is martial art where two opponents throw and restrain each other with their bare hands. Therefore, it is assumed that a judo player needs great strength, especially grip strength. According to a judo text for coaching, a judo player should tightly grasp the judo jacket by mainly the third to fifth fingers and not by five fingers. Additionally, Hikite (a sleeve grip) and Tsurite (a neck grip) exist in the Kumite style of judo. However, research has never been undertaken on the method of grip used and its strength in this sport. Therefore, the purpose of this study was to investigate the relationship between grip and pinch strengths and Kumite in male university judo players.
The subjects of this study were 37 male university judo players. Grip and pinch strengths were measured in both hands of each subject and Kumite (right-handed or left-handed grappling style) investigated by questionnaire. The measurement of pinch strength was double between the first and second fingers compared with the first and fourth fingers.
Grip strength (47.8 ± 6 kg) for Tsurite was significantly greater than that (46.4 ± 6 kg) for Hikite (p < 0.05). Similarly, pinch strength (3.2 ± 2 kg) between the first and second fingers for Tsurite was greater than that (2.9 ± 1 kg) for Hikite (p < 0.05).
The results of this study suggest that in Tsurite, the fourth finger in particular is forced to exert a lasting strength during normal judo practice. This results in muscle hypertrophy and the requirement for a greater grip strength in Tsurite.
Hiroo Takahashi
National Institute of Fitness and Sports in Kanoya, Japan
We investigated the relationship between ball speed and ball spin of tennis strokes of men's professional tennis players. We used Trackman Tennis Radar (Trackman) to measure ball speed and ball spin. Trackman is a radar system to measure ball movement in each shot; such as ball speed, ball spin, spin axis, hitting point, landing point, clearance height at net and so on. Trackman data was collected from the matches of an international tennis tournament held in Japan. Subjected matches were also recorded by video and we identified Trackman data and the shots how players performed from movie. In current study, we analyzed one match by two players (player A and player B). Subjected shots were first serve (n of player A is 25, n of player B is 27), second serve (player A: 11, player B: 8), forehand strokes (player A: 42, player B: 33) and backhand strokes (player A: 27, player B: 32). Slice shots data were excluded from this study. Average of ball speed and ball spin were as follows: player A's first serve: 172.85±7.69km/h and 2774.11±843.66rpm; player A's second serve: 149.30±4.89km/h and 4002.63±246.89rpm; player A's forehand strokes: 114.23±21.54km/h and 2889.47±640.60rpm; player A's backhand strokes: 110.59±12.45km/h and 1602.03±309.63rpm; player B's first serve: 180.94±7.32km/h and 1960.36±646.96rpm; player B's second serve: 140.33±33.19km/h and 3264.73±1219.52rpm; player B's forehand strokes: 125.95±15.34km/h and 1847.28±424.66rpm; player B's backhand strokes: 107.01±10.82km/h and 1391.91±391.60rpm. It was the first study to indicate ball speed and ball spin of those strokes in actual tennis matches.
Jae Koo Lee
Dept. of Leisure and Sports, Sahmyook University, Seoul, Korea
The purpose of this study was to analyze the possible associations of two genetic polymorphisms in COL1A1 and MMP3 genes as candidate genes on the anterior cruciate rupture(ACL) of Korean athletes.
A total of 176 Korean individuals including 75 controls and 101 athletes with a history of ACL rupture females were registered in this study. Total genomic DNA from all subjects studied was isolated from peripheral blood, and the genetic polymorphisms in COL1A1 and MMP3 genes were genotyped by using automated analysis machine.
In the case of the rs#1800012 polymorphism in COL1A1 gene, only GG genotype was observed in all subjects studied, and thus, indicated the monomorphic pattern. However, the rs#679620 polymorphism in MMP3 gene was significantly associated with the susceptibility of ACL rupture(p < .038). Especially, the frequency of GG genotype was significantly higher in athletic group with ACL rupture than controls.
Therefore, our data suggest that the rs#679620 polymorphism in MMP3 gene may be one of the useful genetic markers to assess the susceptibility for ACL rupture of athletes. Further studies using larger sample size will be needed to replicate this significant association.