ClassID:

26018

A63B2220/833 - page 3 - CPC Classification

Classification description:

Measuring of physical parameters relating to sporting activity; Special sensors, transducers or devices therefor characterised by the position of the sensor Sensors arranged on the exercise apparatus or sports implement

Recent Application in this class:
#601
20210370151
2021-12-02

Enhanced infrared hockey puck and goal detection system

#602
20210370122
2021-12-02

Remote-sensing, Bluetooth-enabled resistance exercise band

#603
20210362027
2021-11-25

BALL SPIN RATE MEASUREMENT SYSTEM AND METHOD

#604
20210354024
2021-11-18

COMBINED DIGITAL SCOREKEEPER AND VIBRATION DAMPENER

#605
20210354021
2021-11-18

Squash ball launching machine

#606
20210354014
2021-11-18

Illuminated rim for roundnet

#607
20210346780
2021-11-11

Game Device For Converting A Container Into A Wirelessly Connected Game Figure

#608
20210346754
2021-11-11

TREADMILL ARRANGEMENT WITH MOTION-ADAPTIVE VIRTUAL RUNNING ENVIRONMENT

#609
20210343390
2021-11-04

Tennis racket sensor system and coaching device with ball machine integration

#610
20210339111
2021-11-04

Training module

#611
20210339080
2021-11-04

AUTOMATIC SPEED CONTROL FOR TREADMILL

#612
20210339078
2021-11-04

Compact high resistance fitness device

#613
20210331057
2021-10-28

Swing analysis system that calculates a rotational profile

#614
20210331038
2021-10-28

Dynamic motion resistance module

#615
20210331031
2021-10-28

Exercising apparatus with a limb support, and method for determining the force acting on a limb support of an exercising apparatus

#616
20210322851
2021-10-21

Exercise information management system and method of controlling the same

#617
20210316202
2021-10-14

DEVICE FOR DETECTING THE IMPACT QUALITY IN CONTACT SPORTS

#618
20210316197
2021-10-14

Interactive sports training system and method

#619
20210308524
2021-10-07

Strength training workout tracking device and method

#620
20210308520
2021-10-07

Apparatus for human gait manipulation

#621
20210299542
2021-09-30

Leaderboard with irregularity flags in an exercise machine system

#622
20210299531
2021-09-30

Swing measuring attachment, and swing measuring apparatus

#623
20210291015
2021-09-23

Exercise system and method

#624
20210291014
2021-09-23

Treadmills with obstacles and methods of use

#625
20210291013
2021-09-23

Systems and methods for treadmill drift avoidance

#626
20210283476
2021-09-16

Identifying the sweet spot of a bat

#627
20210279382
2021-09-09

Activities data modeling in human internet-of-things platforms

#628
20210275890
2021-09-09

APPARATUS FOR TRAINING GOLF

#629
20210268353
2021-09-02

Wedge golf club fitting system

#630
20210268329
2021-09-02

DEVICE FOR PHYSICAL EXERCISE

#631
20210260451
2021-08-26

GOLF FLAGSTICK DEVICE FOR DETERMINING A GIMME PUTT

#632
20210260445
2021-08-26

AUXILIARY DRIVE FOR A TRAINING DEVICE

#633
20210252370
2021-08-19

Sport design, tracking, and community system

#634
20210252368
2021-08-19

Infrared hockey puck and goal detection system

#635
20210252336
2021-08-19

Analyzing sensor data associated with athletic equipment

#636
20210252333
2021-08-19

DISPLAY DEVICE AND CONTROL METHOD THEREFOR

#637
20210245011
2021-08-12

Balance training system, method of controlling the same, and control program

#638
20210245010
2021-08-12

Balance training system, method of controlling the same, and controlling program

#639
20210245009
2021-08-12

Balance training system, method of controlling the same, and control program

#640
20210244998
2021-08-12

System, method and apparatus for electrically actuated pedal for an exercise or rehabilitation machine

#641
20210244995
2021-08-12

Kinetic workout station

#642
20210236895
2021-08-05

Multi-sport sensing system

#643
20210236881
2021-08-05

Exercise machine for form training system

#644
20210236876
2021-08-05

Fitness training apparatus and system

#645
20210228963
2021-07-29

Swing quality measurement system

#646
20210228938
2021-07-29

Fluid-damped direct-drive bicycle riding platform and use method thereof

#647
20210228929
2021-07-29

Self-powered, mechanically-isolated/decoupled vibration mechanism for bicycle pedals

#648
20210220715
2021-07-22

Computer implemented American soccer training and evaluation method and system

#649
20210220704
2021-07-22

Weightlifting machine and method of use

#650
20210220703
2021-07-22

Strength training equipment

#651
20210213329
2021-07-15

Instrumented resistance exercise device

#652
20210213327
2021-07-15

Swing analysis device, swing analysis method, and swing analysis system

#653
20210205658
2021-07-08

EXERCISE SYSTEM

#654
20210197057
2021-07-01

METHODS AND DEVICES FOR INTERACTIVE EXERCISING

#655
20210197046
2021-07-01

Smart system for display of dynamic movement parameters in sports and training

#656
20210197027
2021-07-01

Device for muscles and balance development

#657
20210187377
2021-06-24

Practice aid system

#658
20210187362
2021-06-24

Golf Ball Tracking System

#659
20210187352
2021-06-24

Sensor device for exercise apparatus and methods thereof

#660
20210187350
2021-06-24

KINOPED LOWER EXTREMITY PERFORMANCE IMPROVEMENT, INJURY PREVENTION, AND REHABILITATION SYSTEM

#661
20210187349
2021-06-24

Kinoped lower extremity performance improvement, injury prevention, and rehabilitation system

#662
20210178208
2021-06-17

System and method for exercise equipment hinge

#663
20210170214
2021-06-10

Digital strength training

#664
20210170213
2021-06-10

Digital strength training

#665
20210170212
2021-06-10

Racking and unracking exercise machine

#666
20210169372
2021-06-10

Method and apparatus for sports and muscle memory training and tracking

#667
20210162292
2021-06-03

Electronic tracking system with heads up display

#668
20210162270
2021-06-03

Device for displaying in response to a sensed motion

#669
20210162269
2021-06-03

Device for displaying in response to a sensed motion

#670
20210154558
2021-05-27

Swim AR goggles

#671
20210154556
2021-05-27

APPAREL BASED DYNAMIC MOVEMENT SCORING

#672
20210154554
2021-05-27

Systems and devices for training a tennis serve

#673
20210154551
2021-05-27

Golf swing training apparatus

#674
20210153474
2021-05-27

Control method for treadmill

#675
20210153469
2021-05-27

Treadmill having sensors

#676
20210153468
2021-05-27

Portable and storable treadmill having handle

#677
20210153466
2021-05-27

Treadmill having fragrance assembly

#678
20210153465
2021-05-27

Treadmill having deodorizer

#679
20210153464
2021-05-27

Treadmill having sterilizer

#680
20210153463
2021-05-27

Treadmill

#681
20210146215
2021-05-20

Tethered resistance swim training apparatus with smart pulley

#682
20210146193
2021-05-20

INTELLIGENT SPORTS EQUIPMENT SYSTEMS AND METHODS

#683
20210146189
2021-05-20

ERGONOMIC HANDHELD WEIGHT UNIT AND METHOD OF USE

#684
20210138333
2021-05-13

Method and apparatus for false start detection

#685
20210138323
2021-05-13

Golf club heads

#686
20210138308
2021-05-13

SPORTS BALL HAVING ELECTRONICS AND METHOD FOR MAKING

#687
20210138302
2021-05-13

ACTIVITY TRACKING AND MOUNTING APPARATUS AND METHOD FOR USE WITH ACTIVITY TRACKING VIRTUAL WALK E-COMMERCE MOBILE APPLICATION

#688
20210129001
2021-05-06

Indoor-traditional crack climbing hold

#689
20210128989
2021-05-06

Ball retrieval system and method

#690
20210128971
2021-05-06

SENSOR EQUIPPED RESISTANCE TRAINING GRIP

#691
20210128963
2021-05-06

Therapeutic isometric testing and isotonic training exercise device

#692
20210124028
2021-04-29

Predictive maintenance of exercise machines with time-of-flight sensors

#693
20210121756
2021-04-29

Ball game apparatus using a racquet and method of using the same

#694
20210113906
2021-04-22

Apparatus and method for repetitive training of golf swing with virtual reality

#695
20210113892
2021-04-22

Bluetooth enabled ball analyzer and locator

#696
20210113885
2021-04-22

OVERHEAD HANDLEBAR ASSEMBLY FOR AN EXERCISE APPARATUS

#697
20210113152
2021-04-22

Systems and methods of treating proprioceptive dysfunction and vestibular disorders

#698
20210106863
2021-04-15

Electromagnetic resistance feedback system for bicycle training device

#699
20210102852
2021-04-08

TORQUE MEASURING DEVICE FOR A FLYWHEEL

#700
20210101066
2021-04-08

Golf club fitting apparatus

#701
20210101065
2021-04-08

Golf club fitting apparatus

#702
20210101062
2021-04-08

Basketball Training Device

#703
20210095948
2021-04-01

Apparatus for checking golf divot

#704
20210093909
2021-04-01

Gymnastic training apparatus and methods

#705
20210086056
2021-03-25

Tennis racket sensor system and coaching device

#706
20210086052
2021-03-25

Basketball Shooting Training Device

#707
20210086031
2021-03-25

Resistance-band exercise monitoring device and associated methods

#708
20210086030
2021-03-25

Method and system for virtual fitness training and tracking devices

#709
20210086018
2021-03-25

Strength training apparatus

#710
20210084459
2021-03-18

Smart device

#711
20210077889
2021-03-18

Protection device and related method of use

#712
20210077862
2021-03-18

System and method for playing a pin based game using an impact resistant ball and process of forming the same

#713
20210077857
2021-03-18

Indoor bicycle training device

#714
20210077856
2021-03-18

Indoor training bicycle device

#715
20210069546
2021-03-11

Kinoped lower extremity performance improvement, injury prevention, and rehabilitation system

#716
20210060380
2021-03-04

Indoor training bicycle device

#717
20210060378
2021-03-04

Rowing exercise machines having a configurable rowing feel

#718
20210060377
2021-03-04

BAND RESISTANCE STRENGTH PLATFORM

#719
20210060372
2021-03-04

EXERCISE BICYCLE BRAKE ASSEMBLY FOR PROVIDING VARIABLE BRAKING SIGNALS

#720
20210052941
2021-02-25

Bicycle exercise measurement device and bicycle

#721
20210046357
2021-02-18

Device power saving during exercise

#722
20210038961
2021-02-11

Method of conducting interactive computer sports on and off the internet

#723
20210038938
2021-02-11

Exercise machine with pancake motor

#724
20210038937
2021-02-11

Exercise machine with pancake motor

#725
20210034143
2021-02-04

Motion device for virtual reality interaction and virtual reality system

#726
20210031081
2021-02-04

System and method for object tracking in coordination with a ball-throwing machine

#727
20210031071
2021-02-04

Systems and methods for storing and analyzing golf data, including community and individual golf data collection and storage at a central hub

#728
20210023433
2021-01-28

Golf swing playing aid device

#729
20210023412
2021-01-28

Barbell spotting apparatus

#730
20210016150
2021-01-21

DEVICE AND METHOD FOR RECOGNIZING FREE WEIGHT TRAINING MOTION AND METHOD THEREOF

#731
20210016142
2021-01-21

Golf club and golf club head structures

#732
20210016129
2021-01-21

Barbell spotting apparatus

#733
20210016122
2021-01-21

Exercise management device using hula hoop having device for measuring spinning direction and exercise amount

#734
20210008422
2021-01-14

Grip with electronic system and exterior venting

#735
20210008414
2021-01-14

A METHOD AND SYSTEM FOR MEASURING A ROWING PROFILE

#736
20210008411
2021-01-14

LUNG CLEARING AND BODY BUILDING MACHINE

#737
20210008410
2021-01-14

Movement therapy apparatus

#738
20210008402
2021-01-14

Exercise machine with pancake motor

#739
20210008401
2021-01-14

Exercise machine with pancake motor

#740
20210005106
2021-01-07

Motion support system, action support method, program, learning apparatus, trained model, and learning method

#741
20210003463
2021-01-07

Apparatus, system and method for power measurement at a crank axle and crank arm

#742
20210001196
2021-01-07

Practice aid system

#743
20210001180
2021-01-07

Techniques for providing customized exercise-related recommendations

#744
20200406107
2020-12-31

Smart ball

#745
20200398139
2020-12-24

Compact ball launching system and associated methods

#746
20200398113
2020-12-24

Time-of-flight ranging device

#747
20200398111
2020-12-24

Intelligent sports equipment systems and methods

#748
20200391095
2020-12-17

Addressable lighting and scorekeeping system

#749
20200391084
2020-12-17

Sports ball with electronics housed in shock-absorbing carrier

#750
20200384316
2020-12-10

Method of unlocking a control unit of an exercise machine and exercise machine implementing such method

#751
20200376343
2020-12-03

Safety device for assisting a user to traverse a structure

#752
20200376328
2020-12-03

Rowing exercise machines having a configurable rowing feel

#753
20200376321
2020-12-03

Barbell spotting apparatus

#754
20200376320
2020-12-03

Automatic weight adjustable dumbbell

#755
20200376319
2020-12-03

Workout systems and methods using robust door mounting

#756
20200368601
2020-11-26

Tennis racket sensor system and coaching device

#757
20200368581
2020-11-26

Actuator-based exercise and training device

#758
20200368578
2020-11-26

STEP-COUNTING TREADMILL

#759
20200360789
2020-11-19

Real time sports motion training aid

#760
20200360779
2020-11-19

Grip assembly for sports equipment

#761
20200356146
2020-11-12

Detecting a gesture made by a person wearing a wearable electronic device

#762
20200353334
2020-11-12

Interactive electronic table tennis game

#763
20200353313
2020-11-12

PEDAL STRUCTURE FOR EXERCISE BIKE

#764
20200353305
2020-11-12

OPERATING HANDLE OF EXERCISER

#765
20200353303
2020-11-12

Weight-supporting apparatus, system, and method of using the same

#766
20200346119
2020-11-05

Method of transmitting sensor data created in a game environment to a set of processors outside the game environment based on predefined

#767
20200342975
2020-10-29

Exercise machine monitoring system for monitoring one or more exercise machines

#768
20200338389
2020-10-29

Strength training apparatus

#769
20200338383
2020-10-29

Spinner bike with adjustable magnetic resistance

#770
20200338382
2020-10-29

MODULAR HOOP ILLUMINATED CONNECTOR

#771
20200330850
2020-10-22

Sports Training System

#772
20200330849
2020-10-22

Systems and methods for coordinating musculoskeletal and cardiovascular or cerebrovascular hemodynamics

#773
20200330847
2020-10-22

Exercise machine safety enhancements

#774
20200330830
2020-10-22

Golf Ball Tracking System

#775
20200330825
2020-10-22

Resistance sensing apparatus for exercise equipment

#776
20200330819
2020-10-22

Braking and locking system for a treadmill

#777
20200324167
2020-10-15

Method for quantifying a sporting activity

#778
20200324162
2020-10-15

Training apparatus with swivel step plate

#779
20200323476
2020-10-15

Testing and training apparatus

#780
20200316434
2020-10-08

Device and method for enhancing user operation of an exercise machine

#781
20200316424
2020-10-08

Digital strength training

#782
20200306610
2020-10-01

Swing analysis method and swing analysis device

#783
20200306602
2020-10-01

Sports equipment with alterable characteristic

#784
20200306595
2020-10-01

Bluetooth enabled ball analyzer and locator

#785
20200306586
2020-10-01

Golf Green Camera System

#786
20200303958
2020-09-24

Wireless power-feeding apparatus

#787
20200298094
2020-09-24

Autonomous personalized golf recommendation and analysis environment

#788
20200298060
2020-09-24

SYSTEM AND METHOD FOR THE MEASURE OF IMPACT KINETICS

#789
20200298049
2020-09-24

Exercise machine enhancements

#790
20200289910
2020-09-17

Football training tool

#791
20200289894
2020-09-17

Balance training system, control method, and program

#792
20200289893
2020-09-17

Balance training apparatus and control program of balance training apparatus

#793
20200289892
2020-09-17

Exercise device to promote, measure and analyze leg movements while seated

#794
20200289889
2020-09-17

Bendable sensor device for monitoring joint extension and flexion

#795
20200289881
2020-09-17

Control system for a rehabilitation and exercise electromechanical device

#796
20200289880
2020-09-17

System, method and apparatus for electrically actuated pedal for an exercise or rehabilitation machine

#797
20200289879
2020-09-17

System, method and apparatus for a rehabilitation machine with a simulated flywheel

#798
20200289051
2020-09-17

Systems and methods for coordinating musculoskeletal and cardiovascular hemodynamics

#799
20200289046
2020-09-17

Monitoring joint extension and flexion using a sensor device securable to an upper and lower limb

#800
20200289045
2020-09-17

Single sensor wearable device for monitoring joint extension and flexion

#801
20200282286
2020-09-10

Infrared hockey puck and goal detection system

#802
20200282282
2020-09-10

Basketball training assembly

#803
20200276465
2020-09-03

Exercise machine with lockable translatable mount

#804
20200269108
2020-08-27

Inverted dunk tank

#805
20200269079
2020-08-27

Exercise apparatus

#806
20200261763
2020-08-20

Display device and control method therefor

#807
20200254294
2020-08-13

Devices for exercise apparatuses

#808
20200238686
2020-07-30

Liquid discharge head and liquid discharge apparatus provided with the same

#809
20200238136
2020-07-30

Swimming paddle

#810
20200238129
2020-07-30

Virtual inertia enhancements in bicycle trainer resistance unit

#811
20200238128
2020-07-30

Exercise machine enhancements

#812
20200230482
2020-07-23

Swing quality measurement system

#813
20200215406
2020-07-09

Interactive component for an amusement park

#814
20200215391
2020-07-09

Method for determining running phases of a user on a treadmill and treadmill implementing such method

#815
20200206568
2020-07-02

Posture coaching system and method for weight training by motion pattern

#816
20200197782
2020-06-25

Adaptive tennis ball machine

#817
20200197775
2020-06-25

Capacitive sensing climbing hold, associated production method and wall

#818
20200197758
2020-06-25

HEADSET VISUAL DISPLACEMENT FOR MOTION CORRECTION

#819
20200191324
2020-06-18

Goal securement system and method

#820
20200179789
2020-06-11

Braking and locking system for a treadmill

#821
20200179761
2020-06-11

Device power saving during exercise

#822
20200179753
2020-06-11

Real time golf swing training aid

#823
20200171372
2020-06-04

System and method for conducting a performance test of an athlete

#824
20200164262
2020-05-28

Electronic tracking system with heads up display

#825
20200164246
2020-05-28

Single-arm workout body conditioning machine

#826
20200155891
2020-05-21

Wearable resistance training device

#827
20200151838
2020-05-14

Athletic activity user experience and environment

#828
20200147473
2020-05-14

IMPACT SENSING MOUTHGUARD

#829
20200147471
2020-05-14

Golf training aid apparatus and method

#830
20200147456
2020-05-14

Device for displaying in response to a sensed motion

#831
20200147452
2020-05-14

Exercise apparatus

#832
20200147450
2020-05-14

Torque-measuring system and body training equipment with the same

#833
20200139202
2020-05-07

Device for displaying in response to a sensed motion

#834
20200139201
2020-05-07

Device for displaying in response to a sensed motion

#835
20200139200
2020-05-07

Device for Displaying in Response to a Sensed Motion

#836
20200139195
2020-05-07

Adjustable proprioceptive neuromuscular trainer

#837
20200139190
2020-05-07

WEARABLE EXERCISE APPARATUSES

#838
20200129825
2020-04-30

Wedge golf club fitting system

#839
20200129818
2020-04-30

Device for displaying in response to a sensed motion

#840
20200129817
2020-04-30

Device for Displaying in Response to a Sensed Motion

#841
20200114242
2020-04-16

CYCLIST RELATIVE PERFORMANCE MEASUREMENT APPARATUS

#842
20200108293
2020-04-09

Trampoline for use as an input device for an electronic game

#843
20200101367
2020-04-02

Smart device

#844
20200101345
2020-04-02

Muscle training apparatus capable of generating force

#845
20200094122
2020-03-26

Information processor and information processing method

#846
20200094113
2020-03-26

Device for displaying in response to a sensed motion

#847
20200094112
2020-03-26

Device for displaying in response to a sensed motion

#848
20200086194
2020-03-19

Basketball performance monitoring system

#849
20200078655
2020-03-12

Digital putting diagnosis device

#850
20200078649
2020-03-12

Apparatus and methods to track sport implements

#851
20200078639
2020-03-12

Systems and methods for storing and analyzing golf data, including community and individual golf data collection and storage at a central hub

#852
20200070028
2020-03-05

Sports throwing motion training device

#853
20200070019
2020-03-05

Monitoring device for a piece of sports equipment

#854
20200054929
2020-02-20

Interactive exercise machine support and mounting system

#855
20200054925
2020-02-20

Device and method for teaching/training golf

#856
20200054914
2020-02-20

Racking and unracking exercise machine

#857
20200047055
2020-02-13

Interactive exercise machine with social engagement support

#858
20200047054
2020-02-13

Interactive exercise machine data architecture

#859
20200047053
2020-02-13

Force feedback arm for an interactive exercise machine

#860
20200047052
2020-02-13

Infrared hockey puck and goal detection system

#861
20200047030
2020-02-13

Interactive exercise machine system with mirror display

#862
20200047027
2020-02-13

User interface system for an interactive exercise machine

#863
20200038732
2020-02-06

FULL SCALE PRACTICE AND TRAINING SYSTEM METHOD AND SOFTWARE MEDIUM UTILIZING PROGRAMMABLE CHASSIS DRIVEN DRONES AND TACKLING DUMMIES IN SINGULAR AND MULTIPLE VARIANTS SUCH AS FOR USE BY POSITIONAL PLAYERS IN SOLE AND TEAM-BASED SPORTS AS WELL AS OTHER NON-ATHLETIC TRAINING APPLICATIONS

#864
20200038729
2020-02-06

SYSTEM AND METHOD FOR TARGET DETECTION

#865
20200034677
2020-01-30

Electronic tag

#866
20200030661
2020-01-30

Motion capture and analysis

#867
20200027180
2020-01-23

Athletic activity user experience and environment

#868
20200023254
2020-01-23

Annular multimedia stadium goalpost and multipurpose target display system

#869
20200023239
2020-01-23

Gamification balance exercise system

#870
20200016464
2020-01-16

Analysis apparatus, analysis method, and recording medium

#871
20200016458
2020-01-16

SENSOR MAT FOR ATHLETES

#872
20200009442
2020-01-09

Device for improving position and posture during weight-lifting exercise in sports

#873
20200008410
2020-01-09

Fly rod including cast sensors

#874
20200008023
2020-01-02

Smart device

#875
20200004322
2020-01-02

Mixed-reality golf tracking and simulation

#876
20200001161
2020-01-02

Water flow control device for swimming training

#877
20200001154
2020-01-02

Golf club head

#878
20190388763
2019-12-26

Ball return device and method of using

#879
20190388760
2019-12-26

Interactive exercise and training system

#880
20190381384
2019-12-19

Electronic tracking system with heads up display

#881
20190381382
2019-12-19

Boxing fitness device and detection method thereof

#882
20190374840
2019-12-12

Systems and methods for coordinating musculoskeletal and cardiovascular or cerebrovascular hemodynamics

#883
20190374835
2019-12-12

Ball spin rate measurement system and method

#884
20190374808
2019-12-12

FLYWHEEL MEASURING SYSTEM AND FITNESS EQUIPMENT HAVING THE SAME

#885
20190358515
2019-11-28

Blockchain

#886
20190358481
2019-11-28

Bottomless pole vault training box

#887
20190351309
2019-11-21

Braking system for a treadmill

#888
20190351308
2019-11-21

Locking system for a treadmill

#889
20190351307
2019-11-21

Treadmill with lighting and safety features

#890
20190351300
2019-11-21

Sports training system

#891
20190346320
2019-11-14

Power measurement device

#892
20190344134
2019-11-14

Golf club and golf club head structures

#893
20190344123
2019-11-14

Strength training and exercise platform

#894
20190336825
2019-11-07

Systems and methods for real-time data quantification, acquisition, analysis, and feedback

#895
20190336823
2019-11-07

Hinged arm muscle exercise device

#896
20190329117
2019-10-31

Sports equipment comprising a guy line and a measuring apparatus fastened to the guy line

#897
20190324423
2019-10-24

Ball-pitching control method of pitching machine in baseball practice system and baseball practice system using the same

#898
20190323655
2019-10-24

Goal securement system and method

#899
20190321710
2019-10-24

Method for delivering sports telemetry for a curling game

#900
20190321684
2019-10-24

Ball-pitching control method of pitching machine in baseball practice system and baseball practice system using the same