Journal of Exercise Physiologyonline

125

Journal of Exercise Physiology online

December 201 8 Volume 21 Number 6

EditorOfficial- in Research- Chief Journal of JEP online Tommythe American Boone , PhD Society, MBA of ReviewExercise Board Physiologists Exercise I ntensity of Kung Fu G ymnastics in A mateur Todd Astorino, PhD Julien Baker,ISSN 1097 PhD - 9751 P ractitioners : Comparison to Tai Chi Chuan Steve Brock, PhD Lance Dalleck, PhD Meng Fan 1 , Naoyuki Yamashita 1, 2 , Hiroki Matsuoka 3 , Takaaki Eric Goulet, PhD Matsumoto 1 Robert Gotshall, PhD Alexander Hutchison, PhD 1 M. Knight - Maloney, PhD Laboratory for Exercise Physiology and Biomechanics, Graduat e Len Krav itz, PhD School of Health and Sport Sciences, Chukyo University, Toyota, James Laskin, PhD Japan, 2 Faculty of Arts and S ciences, Kyoto Institute of Technology , Yit Aun Lim, PhD Kyoto, Japan , 3 Department of Modern Chinese Studies, Faculty of Lonnie Lowery, PhD Derek Marks, PhD Modern Chinese Studies, Aichi University, Nagoya, Japan Cristine Mermier, PhD Robert Robergs, PhD ABSTRACT Chantal Vella, PhD Fan M, Yamashita N, Matsuoka H, Matsumoto T. Exercise Dale Wagner, PhD I ntensity of Kung Fu G ymnastics in A mateur P ractitioners : Frank Wyatt, PhD Ben Zhou, PhD Comparison to Tai Chi Chuan . JEP online 20 1 8 ; 21 ( 6 ): 125 - 133 . The purpose of this study was to examine the exercise intensity of a practi ce routine of Chang Chuan , which is generally called Kung Fu gymnastics. Ten healthy subjects (3 men and 7 women) in their 30s and 40s who had practiced Tai Chi Chuan and Kun g Fu gymnastics Official Research Journal of the American Society of for 2 y rs performed Kung Fu gymnastic s 1 and Kung Fu gymnastic s Exercise Physiologists 2 for 2 min and 24 forms Tai Chi Chuan for 6 min. Breathing frequency, expired ventilation , and oxygen consumption were ISSN 1097 - 9751 measured with a portable device. Exercise intensity and heart rate was 5.6 ± 1.6 METs and 119 ± 13 b eats·min - 1 during Kung Fu gymnastics a nd 3.9 ± 0.9 METs and 105 ± 12 beats·min - 1 during Tai Chi exercises (P<0.01). Breathing frequency, expired ventilation and forearm accelerations during Kung Fu gymnastics were significantly higher than in the Tai Chi exercises (P<0.01). Moreover, it was fo und that forearm acceleration dynamically changed throughout Kung Fu gymnastics, while it was relatively stable during the Tai Chi exercises. This is the first report that shows the exercise intensity of Kung Fu gymnastics or Chang Chuan. Because of its hi gher exercise intensity and simpler movements, Kung Fu gymnastics might be more suitable than Tai Chi Chuan to introduce for the beginners, particularly for young to middle - aged people.

Key Words : Exercise Intensity, Forearm Acceleration, Kung Fu Gymnast ics, Tai Chi Chuan 126

INTRODUCTION

The Chinese martial art "Chang Chu an (Long Fist)" or "Chang Quan" has a long history. It was originated , and is still popular in the northern China (north of Yangze River) including Cha Quan, Hua Quan, Hong Quan, Shaolin Q uan, Fanzi Quan , and Pao Chui. It is characterized by open and long - range strikes, and wide variety of leg techniques and circular motions. It util izes open and expanded postures and high speed techniques as well as many aerial and acrobatic moves . It is a fast, dynamic , and exciting style that incorporat es many breathtaking movements (20). It is helpful for training the body and the spirit in terms of speed, power, jumping, starting power, agility, flexibility, stamina, cooperativeness, etc. Despite these benefits, however, Chang Chuan is not prevailing compared to Tai Chi Chuan (21), which is the most widely practiced and popular martial art in the world. Exercise intensity and physiological impacts on the body are relatively unknown in Chang Chuan.

In 19 96, Wushu Federation of Asia established 4 kinds of practice routine of Chang Chuan and named them "Kung Fu gymnastics 1", "Kung Fu gymnastics 2", "Introductory Chang Chuan", and "Elementary Chang Chuan", based on the proposal of Japan Wushu Taijiquan Fede ration, aiming for the prevale nce of Chang Chuan in Japan (7, 8). Thereafter, the number of Chang Chuan practitioner has increas ed among Japanese from middle - aged people to children.

Tai Chi Chuan, on the other hand, is the most widely practiced and popula r martial art in the world. It is characterized by slow and graceful motions and a combination of both hard and soft techniques. It is comprised of well - known styles such as Chen, Yang, Wu, Sun and Wu (Hao), and is popular due to its health building and lo ngevity benefits. It is defined by slow motions coupled at times with explosive bursts of force, which require total harmony of motion and breath, concentration , and co - ordination of the entire body and spirit in a continuous practice (20) . Many studies ha ve investigated the positive health effects of Tai Chi Chuan for healthy elderly (14), as well as for patients (2). Such health benefits include improvement in aerobic fitness and energy metabolism, muscle strength and b alance, and mental control (14, 16,17 ).

However, it is not easy for healthy elderly or even for young beginners to learn Tai Chi Chuan because its forms are complex and it requires many different motions of both the upper and the lower extremities at the same time, though the movements are s low and calm. Exercise intensity of Tai Chi Chuan has been reported to be relatively low as 3.0 METs on average (1).

I n contrast, the Kung Fu gymnastics practice routines of Chang Chuan are easier to learn because the movements are simple compared to Tai Chi Chuan. Furthermore, a modified exercise program of Tai Chi Chuan combined with Kung Fu gymnastics could be more efficient than the current Tai Chi Chuan in the improvement of physical fitness (5).

For those reasons, Kung Fu gymnastics are more suitabl e than Tai Chi Chuan to introduce to beginners, particularly people in their 30s and 40s . According to our knowledge, there are no studies that show the exercise intensity of Kung Fu gymnastics, nor of Chang Chuan.

In this study, therefore, exercise inten sity of Kung Fu gymnastics was examined to provide the scientific bases for the propagation of Kung Fu gymnastics and Chang Chuan. 127

METHODS

Subjects Ten healthy people in their 30s and 40s, 3 men (age, 44.7 ± 3.2 yrs; height, 177.9 ± 6.8 cm; body mass, 68 .5 ± 7.2 kg; mean ± SD) and 7 women (age, 39.6 ± 4.7 yrs; height, 157.6 ± 5.5 cm; body mass, 51.5 ± 4.0 kg) volunteered to participate in this study . All subjects had practiced Yang style Tai Chi Chuan and Kung Fu gymnastics under the supervision of an exp erienced instructor onc e a week for approximately 2 y rs. All subjects gave their written informed consent, after they were fully informed about the purpose of the study. The present study was approved by the Human Subjects Committee at Chukyo University Gr aduate School of Health and Sports Sciences.

Procedures All measurements were carried out at the Laboratory for Exercise Physiology and Biomechanics in the Graduate School of Health and Sports Sciences at Chukyo University. Upon reporting to the laborator y, the subjects’ height and body mass were measured. After warming - up, each subject perf ormed Kung Fu gymnastics and 24 - form Tai Chi Chuan in a random or der, inserting a rest of 2 to 3 h rs.

Exercise The subjects, under instruction, performed Kung Fu gymna stics 1 and Kung Fu gymnastics 2 that last ed for 20 to 25 sec , respectively, with some repetitions, for 2 min in total. 24 - form Tai Chi Chuan was performed with music for 6 min.

Measurements Breathing frequency (Fb) , expired ventilation (V E ) , and oxygen c onsumption (VO 2 ) were measured using a Metamax 3B portable system with MaxSport Jacket and Triple V volume transducer (Cortex, Leipzig, Germany) during 3 min of sitting - rest and 3 min of standing - rest, and exercise. The VO 2 values were standardized for tem perature and pressure dry (STPD) prior to calculat ion . The measurement system was calibrated according to the manufacturer's recommendations. Heart rate (HR) and tri - axial acceleration were also measured using a heart rate transmitter (Polar, Helsinki, Fin land) fixed on the thorax and a tri - axial accelerometer (RF - BBC, Medical Electronic Science Institute Co. Ltd, Tokyo, Japan) was attached to the dorsal aspect of the distal end of right forearm, respectively.

Statistical Analyses The d ata were expressed a s mean ± standard deviation (SD) in tabular and graphical formats. All data were statistically analyzed using the SPSS software ver.12 (SPSS, Chicago, IL, USA). Differences between Kung Fu gymnastics and Tai Chi Chuan were assessed using a paired t - test. T he significance level was set at P <0.05.

RESULTS

Changes in VO 2 during Kung Fu gymnastics (2 min) and during Tai Chi exercises (6 min) are shown in Figure 1. In Kung Fu gymnastics, VO 2 rapidly increased as soon as the subjects started the exercise and re ached the plateau at the latter half. In the Tai Chi exercises, VO 2 gradually increased and remained low throughout the exercise . 128

Figure 1. Changes in O xygen C onsumption during Kung Fu G ymnastics (2 min) and Tai Chi Chuan (6 mi n). Values are expressed as mean ± SD.

Three - dimensional acceleration of the forearm was measured using a three - dimensional accelerometer. Figure 2 shows changes in three - dimensional acceleration during Kung Fu gymnastics and during Tai Chi exercises. A c lear difference lies between the two; forearm acceleration changed dynamically throughout the duration of Kung Fu gymnastics, while it remained relatively stable during Tai Chi exercises.

Figure 2. Changes in T hree - D imensional A cceleration of the F orearm during Kung Fu G ymnastics (2 min) and Tai Chi Chuan (6 min). Values are expressed as mean ± SD.

- 1 - 1 There were no gender differences in VO 2 : 23.5 ± 7.5 mL·kg ·min in the men (n = 3) and 17.7 ± 2.7 mL·kg - 1 ·min - 1 in the women (n = 7) during Kung Fu gymnastics ( P =0.31) and 15.7 ± 2.5 mL·kg - 1 ·min - 1 in the men (n = 3) and 12.6 ± 1.8 mL·kg - 1 ·min - 1 in the women (n = 7) during Tai Chi exercises ( P =0.14). Th us , the data for both the men and the women are combined for further analysis. Th e m ean VO 2 during sitting - rest and standing - rest were 4.4 ± - 1 - 1 - 1 - 1 0.6 mL·kg ·min and 4.8 ± 0.6 mL·kg ·min , respectively. The a verage values in VO 2 - 1 - 1 - 1 - 1 (m L· kg · min ), exercise intensity (METs), HR ( beats·min ), Fb (cpm), V E (L ·min ) , and 129 forearm acceleratio ns ( m· sec - 2 ) during Kung Fu gymnastics and during Tai Chi exercises are shown in Table 1. All the measurements in Kung Fu gymnastics were significantly larger than those in Tai Chi exercises (P<0.01).

Table 1. Oxygen Consumption, Exercise Intensity, Heart Rate, Breathing Frequency, Ventilation and Forearm Acceleration during Kung Fu Gymnastics and Tai Ch i Chuan. Kung Fu Tai Chi Chuan P G ymnastics Oxygen Consumption ( mL·kg - 1 ·min - 1 ) 19.1 ± 5.6 13.5 ± 3.0 P<0.01

Exercise Intensity (METs) 5.6 ± 1.6 3.9 ± 0.9 P<0.01

Heart Rate ( beats·min - 1 ) 119 ± 13 105 ± 12 P<0.01

Breathing Frequency (cpm) 29.3 ± 5.6 21.7 ± 7.4 P<0.01

Ventilation (L ·min - 1 ) 26.0 ± 8.9 19.6 ± 5.9 P<0.01

Forearm Acceleration ( m·sec - 2 ) 2.57 ± 1.1 1.64 ± 0.3 P<0.01

DISCUSSION

In the pr esent study, 10 amateur practitioners in their 30s and 40s performed Kung Fu gymnastics (i.e., they practice d a routine of Chang Chuan ) and Tai Chi exercises. Exercise intensity of Kung Fu gymnastics was demonstrated to be 5.6 ± 1.6 METs, which was almost 70% more intense than Tai Chi (3.9 ± 0.9 METs) (Table 1). According to our knowledge, this is the first report that shows exercise intensity of Kung Fu gymnastics or Chang Chuan.

Oxygen consumption, exercise intensity, HR , Fb, and V E were significantly gr eater in Kung Fu gymnastics versus the Tai Chi exercises (Table 1). Perhaps m ore importantly, a clear difference between the two exercises was found in forearm acceleration. It dynamically changed throughout the exercise of Kung Fu gymnastics, while it was relatively stable in Tai Chi exercises (Figure 2). This finding probably reflects the features of Chang Chuan movements , which are characterized by lightning speed, powerfulness, light movements, high jumps, and slow and free motion (21). These results cl early show that exercise intensity in Kung Fu gymnastics is greater than that in Tai Chi exercises.

Exercise intensity and average HR in Tai Chi Chuan and in Kung Fu gymnastics are summarized in Table 2. In 1984, Zhuo et al. (22) reported that the exercis e intensity of 108 forms Tai Chi Chuan was 4.1 ± 0.6 METs amo ng 11 men aged 24 to 35 yrs , which is close to the result of the Tai Chi exercises (3.9 ± 0.9 METs) in the present study. Ainsworth et al. (2011) reported that the exercise intensity of “Thai Chi and Qig o ng, general (code 15670)” was 3.0 METs as the average of 4 measures in 3 reports (3,4, 22) in 2011 Compendium of Physical Activities (1). Also , summarized in Table 2 are 4 studies that reported the exercise intensity of Tai Chi Chuan (6,12,15, 19) n ot including in Ainsworth’s report, 3 studies that reported the average HR during Tai Chi Chuan (10,13, 18), 2 studies that reported the exercise inten sity of Win Chun and Qigong (9, 19). 130

Table 2. Exercise Intensity and Average Heart Rate in Tai Chi Chuan, i ncluding Some Relatives, and Kung Fu Gymnastics (Mean ± SD) . Exercise Author Heart Rate Subjects Exercises Intensity （ y r ）（ beats·min - 1 ）（ METs ）

Zhuo et al 24 to 35 yrs 108 Forms Tai Chi * 4.1 ± 0.6 m ax HR 134 (1984) (n = 11 , M) 22 min 30.0 ± 5.0 yrs Wing Chun 6 .6 ± 2.2 137 ± 25 Schneider et al (n = 1 0, M) 6 min (1991) 35.5 ± 3.9 yrs 108 Forms Tai Chi 4.6 ± 1.1 116 ± 22 (n = 1 0, M) 20 min

Fontana 21 to 49 yrs 8 Forms Tai Chi (slow) 2.3 ± 0.3 - (2000) (M 12, F 14) 8 Forms Tai Chi (fast) 2.6 ± 0. 5 -

Lan et al . 26 - 56 yrs 108 Forms Tai Chi * 6.1 ± 0.4 14 0 ± 1 0 (200 1 ) (n = 15, M) 24 min

Chao et al . 60.7 ± 9.9 yrs Tai - Chi - Qui - Gong M: 3. 6 ± 0. 5 delta HR 21.6 - (2002) (M 13, F 34) 9 min F: 3. 0 ± 0.7 28.8

5 0 .5 ± 5.5 yrs - 137.8 ± 6.4 24 Forms Tai Chi Liu et al . (n = 10, F) exp 6 min (2003) 5 3.6 ± 4.9 yrs - 117.7 ± 6.5 (n = 10, F) begi

5 8.8 ± 7. 9 yrs 108 Forms Tai Chi - 1 29 ± 7 Lan et al . (n = 12, M) 24 min (200 4a ) 5 8.6 ± 6.9 yrs Qigong - 91 ± 5 (n = 12, M) 30 min

M: 14 0 ± 1 0 25 to 44 yrs - F:136 ± 1 0 (M 17, F 12) Lan et al . 108 Forms Tai Chi 45 to 64 yrs M:132 ± 9 (200 4b ) 24 min - (M 20, F 18) F:126 ± 1 1 65 to 80 yrs M: 1 20 ± 1 0 - (M 17, F 16) F:115 ± 1 2

Hui et al . middle age 32 Forms Tai Chi 3.2 ± 0.7 98 ± 1 6 (2009) (n = 30) 10 min

Lee et al . a Tai Chi master 63 108 Forms Tai Chi 4.6 - (2011) yrs

Ladawan et al . 25 to 44 yrs 18 Forms Qigong 1.8 ± 0.2 80.1 ± 6.0 (2018) (n = 10, F)

Present Study 30 to 46 yrs 24 Forms Tai Chi 3.9 ± 0.9 105 ± 12 (M 3, F 7) 6 min Kung Fu gymnastics 5.6 ± 1.6 119 ± 13 2 min

M = M ale, F = F emale , exp = experienced, begi = beginners. *C alculated from the reported value of VO 2 . 131

Lan et al. ( 11 ) indicated that the exercise intensity of Tai Chi Chuan va ries among different styles . As shown in Table 2, the higher in tensity, 4.1 ± 0.6 METs (22), 4.6 ± 1.1 METs (19), 6.1 ± 0.4 METs (12) were reported in classical (108 forms) Tai Chi Chuan with the duration between 20 to 24 min and the slightly lower intensity, 2.3 ± 0.3 METs and 2.6 ± 0.5 METs (4) in 8 forms, 3.2 ± 0.7 METs in 32 forms for 10 min (6) and 3.9 ± 0.9 METs in 24 forms Tai Chi Chuan for 6 min (present study). It is suggested that exercise intensity of Tai Chi Chuan var ies among the styles and also with the duration.

Lan et al. (10 ) measured HR during 108 fo rms Tai Chi exercises in 54 men and 46 women from 25 to 80 yrs old. The heart rate was 141 ± 12 beats·min - 1 in male subjects 25 to 44 yrs old , 132 ± 9 beats·min - 1 in male subjects 45 to 64 yrs old , 120 ± 10 beats·min - 1 in male subjects 65 to 80 yrs old , and the HR was 136 ± 10 beats·min - 1 in female subjects 25 to 44 yrs old , 126 ± 11 beats·min - 1 in female subjects 45 to 64 yrs old , and 115 ± 12 beats·min - 1 in female subjects 65 to 80 yrs old (10). These data suggest that exercise intensity of Tai Chi Chuan is higher in younger practitioners than in the older practitioners , and also higher in the men than in the women.

Liu et al. ( 18 ) measured HR during 24 forms Tai Chi Chuan in 10 experienced and 10 beginner women at the same age class. Heart rate was 137.8 ± 16.4 b eats·min - 1 in the experienced women and 117.7 ± 6.5 beats·min - 1 in the beginners. Lee et al. ( 15 ) measured exercise intensity during 108 forms Tai Chi Chuan in a T ai Chi master aged 63 and revealed that his exercise intensity was 4.6 METs, w hich is comparable to the measurements of the younger subjects, 4.6 ± 1.1 METs in 35.5 ± 3.9 yrs (19) and 4.1 ± 0.6 METs in the subjects aged 24 to 35 y rs (22). These results indicate that exercise intensity of Tai Chi Chuan may increase according to the s kill level of subjects.

Some other researchers have reported the exercise intensity in the other Chinese martial arts (9, 19). Ladawan et al. ( 9 ) reported that exercise intensity in 18 forms of Qigong was 1.8 ± 0.2 METs in female subjects 25 to 44 yrs old. Exercise intensity of Qigong is suggested to be lower than that of Tai C hi Chuan. Schneider et al. (19 ) reported that exercise intensity of Win g Chun was 6.6 ± 2.2 METs in men were 30.0 ± 5.0 yrs of age with a training experience of 50.2 ± 24.0 months and that in 108 forms Tai Chi Chuan was 4.6 ± 1.1 METs in men 35.5 ± 3.9 yrs of age with a training experience of 81.6 ± 40.8 months. Win g Chun, a type of Nan Quan (Southern Fist) (20) is executed with rapid, forceful striking and kicking movements with force d expirations, timed with punching and kicking in attempt to achieve maximum power. Exercise intensity of Kung Fu gymnastics (5.5 ± 1.6 METs) demonstrated in the present study was just lower than that in Wing Chun. Taking the higher age and the shorter tra ining experience of the subjects in the present study into consideration, exercise intensities in Kung Fu gymnastics and in Wing Chun might be considered comparable.

CONCLUSIONS

The purpose of the present study was to examine the exercise intensity of Kun g Fu gymnastics. Exercise intensity of Kung Fu gymnastics was demonstrated to be 5.6 ± 1.6 METs. It is apparent from the result that it is higher than that of Tai Chi Chuan. According to our knowledge, this is the first report that shows the exercise inten sity of Kung Fu gymnastics or Chang Chuan. We hereby suggest that Kung Fu gymnastics can be more suitable than Tai 132

Chi Chuan for beginners, p articularly for those in the age range of 30s and 40s because of the higher exercise intensity and simpler movement s.

ACKNOWLEDG MENTS We are deeply grateful to all the members of Laboratory for Exercise Physiology and Biomechanics, Graduate School of Health and Sports Sciences, Chukyo University for their kind support, and also to Prof essor Tomohiko Murase, Aichi Un iversity, for his valuable comments and advices.

Address for correspondence: Takaaki Matsumoto, MD, PhD, Laboratory for Exercise Physiology and Biomechanics, Graduate School of Health and Sports Sciences, Chukyo University, Toyota, Aichi, Japan, 470 - 039 3 , Email: t - [email protected] - u.ac.jp

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