Usain Bolt phenomenon. Key points of kinematic parameters of technical skills in 100 m run

Фотографии: 

ˑ: 

Associate professor, Ph.D. O.M. Mirzoev1
Associate professor, Ph.D. V.V. Vlasov2
1 Russian State University of Physical Culture, Sport, Youth and Tourism (GTsOLIFK), Moscow
2 Surgut State Pedagogical University, Surgut

Keywords: 100 m distance run, World Cup, semi-final and final races, parts (segments) of distance, kinematic indicators of technical skills: running time and speed, number, length and frequency of progressive run.

Introduction. According to the results of the unofficial team standings, significant changes are marked in the countries that claim to victory in sprint by the final results of world championships and the Olympic Games in the XXI century. While from 2001 till 2007, as well as in the last century, American sprinters were deemed the undisputed leaders, starting from 2008 it is Jamaican sprinters who started to compete with them (the Jamaican female sprinters turned the tide for their own benefit, too, having taken the lead off American female sprinters). It should be added here that, for instance, of 27 Olympic champions in the 100 m run, 17 people (63%) are the representatives of the USA, and of 14 world-strongest sprinters 8 (57.1%) are the US citizens (it is the Jamaican sprinters who won three latest World Cups).

It was at the 2008 Beijing Olympics that the Jamaica's representative first won the 100 m race - success attended Usain Bolt (21.08.1986). That is when the main competition for the leadership in the World Championships and the Olympic Games starts between the American and Jamaican schools of sprint race (among males and females; this refers not only to the 100 m distance run, but also 200 m run and 4x100 m relay race). If we add that in 2012 (London), as well as at the World Championships of 2009 through 2013, we observed the undeniable advantage of U. Bolt (and not limited to him - in 2011 I. Blake became the world champion in the 100 m run, and he trained in one group with the world record-holder), it becomes evident that American hegemony (as the success of the US sprinters was determined in prior years) in the athletics international arena was disturbed by the Jamaicans this time. Similar situation was observed in the 1972 Games in Munich, when Soviet athlete Valeriy Borzov , having gotten ahead of the strongest US athletes, the favorites, won gold in the 100 and 200 m distance run. After V. Borzov's victory American athletes were not able to restore their reputation in the 100 m distance run during the succeeding Olympic Games (no World Championships in athletics were held until 1983).

Starting from 2005, it was only Jamaican sprinters who succeeded to set up the world records in the 100 m run - A. Powell (4, two of which were repeated – 9.77 sec) and U. Bolt (3). By the efforts of these two athletes the world record was bettered by 0.19 sec, whereas from the moment of registration of the world records using the electronic timing system, it is six Americans who succeeded to better it by 0.16 sec.

Similar situation is observed in sprint race among females. Suffice it to recall that at the 2008 Olympic Games the entire victory podium of the 100 m run was occupied by female athletes from Jamaica, at the London Olympics the Jamaican females won gold and bronze, and at the World Championship in the 100, 200 m distance run and 4x100 m relay race, held in Moscow, they once again demonstrated their high class.

As of today, the priority types of athletics for the Jamaican team are the 100, 200 m distance run and 4x100 m relay race. Owing to these types of athletics, the national team of this insular state took, for instance, the third place in the unofficial team standings, among 38 countries that won different medals, at the XIV World Championship in Moscow (2013, including all types of athletics).

All the above mentioned allows looking closely, for instance, at the training program in general, selection of the means of training and their distribution, specifics of planning of a particular training session, as well as analyzing technical skills under competitive conditions, which is studied in the current paper.

The purpose of the research was to study the kinematic characteristics of the running technique of the world-fastest sprinter U. Bolt in 100 m run under competitive conditions.

Results and discussion. It is well known that any change in running speed inevitably affects its basic components. The relationships of the two components that make up the running speed, are examined in this paper.

Normally, it is the analysis of running at the maximum speed that draws the utmost interest, since it is when most indicators of the running technique reach their extreme values. This primarily refers to the length and frequency of progressive run, which are easy to register and are helpful when comparing them with the dynamics of sports result during the distance run. The discussion about the component thanks to which it would be possible to increase (improve) speed has been held for several decades now, starting from the last century. Some insist that athlete's progressive run length extends with improvement of his technical skills, other pay particular attention to the frequency of progressive run.

We were concerned with the issue of the relationship between the progressive run length and its frequency in the athlete who has been the fastest in the 100 m run for many years.

As has already been mentioned, over the past two Olympic cycles U. Bolt has become a prominent representative of the men's school of 100 m run. Starting from 2008, his best result of the season fell behind 10.00 sec (until 2008, the athlete took active part in the 200 m distance run). He was able to reduce his personal result in the 100 m distance run to 9.58 sec, which is the world record today (U. Bolt is also the world record-breaker in the 200 m run - 19.19 sec and joint world record holder in the 4x100 m relay race - 36.84 sec). U. Bolt was the first to set up a specific record by winning the two (in a row) Olympic Games in the 100, 200 and 4x100 m races. In a word, one Olympic cycle that finished in 2012, including the preceding one, as well as the new cycle that started in 2013 in the 100 m run passed under the name of this Jamaican athlete.

The dynamics of sports results achieved by the sprinter year after year is presented in Table 1, and Table 2 represents the best results in his professional career.

Table 1. Dynamics of sports results of U. Bolt in 100 m run

Sl. No

Year

Result,

sec

Wind,

m/s

Percent of the maximal result

1

2014

9.98

- 0.6

95.99

2

2013

9.77

- 0.3

98.05

3

2012

9.63

+ 1.5

99.48

4

2011

9.76

+ 1.3

98.15

5

2010

9.82

+ 0.5

97.55

6

2009

9.58*

+ 0.9

100

7

2008

9.69*

9.72*

0

+ 1.7

--

--

8

2007

10.03

+ 0.7

--

Note to Table 1.

The percent of the best result was calculated based on the achievements of 2009 (9.58 sec)

* - world records.

U. Bolt started to perform in 100 m run more actively from 2007 onwards. Before that the athlete performed mainly at the distances twice as long. From year to date (2007 - 2014) the athlete has improved his personal record by 0.45 sec or 4.70%. By the efforts of this Jamaican sprinter the world record in 100 m distance run has been bettered by 0.16 sec (in general, starting from 2005 the Jamaican sprinters - U. Bolt and A. Powell set seven world records, which once again testifies to the high status of the Jamaican school of sprint race in the world).

Table 2. Best results in U. Bolt's competitive career

Sl. No

Type of athletics

Result,

sec

Date

1

100 m run

9.58

16.09.2009

2

200 m run

19.19

20.08.2009

3

300 m run

30.97

27.05.2010

4

400 m run

45.28

05.05.2007

5

4х100 m relay race

36.84

11.08.201
 

Note to Table 2.

The results of the 100 m, 200 m and 4х100 m distance run are the world records.

Based on the above mentioned, it would be interesting to analyze the kinematic indicators of technical skills (speed components) of the repeated World and Olympic Champion in the 100 m distance run, which were obtained during his performance in the semi-final and final races of the World Cup held in Moscow (11-12.08.2013).

As a rule, 100 m run is divided into four phases (parts); 0-30 m (start and starting stride), 30-60 and 60-80 m (distance run) and 80-100 m (finish). The analysis of the kinematic characteristics of the Jamaican sprinter's running technique in the 100 m run has revealed the following (Table 3).

The high level of physical fitness enabled him to cover all the competition laps (three) with little effort and win gold in the Moscow World Cup. In the main race of the World Championship, compared with the semi-final race, the World Champion managed to improve his sports result by 0.15 sec, notwithstanding the wind pattern changed for the worse - by 0.13 m/sec.

0-30 m part of distance (start and starting stride).

The comparative analysis of the kinematic characteristics of the running technique, which were obtained as a result of the two starts of the world champion (semi-final and final races) has revealed that the difference between the running time in the start and starting stride segment turned out to be insignificant (0.03 sec). Most probably, this (minimum) difference was due to the startle response and wind pattern. The structure of the running technique has changed slightly. The average length of progressive run was equal to 1.99 m in both cases. The percent of the speed gathered of its individual maximum (100%) value has not changed that significantly either.

Table 3. kinematic indicators of technical skills of u. bolt in 100 m run

Parts

(segments)      of distance

Indicators

Competition lap.

Competitive performance

3th  semi-final race.

5th track. wind: + 0.1 m/sec. 11.08.2013. 19.21 hrs.

Final race.

6th track. wind: - 0.3 m/sec. 12.08.2013.  21.51 hrs.

Startle response

0.173 sec

0.163 sec

0 –

30 m

t      

                     3.86                 (2)

                     3.83                 (3)

v         

                     7.77       (65.68%)

                     7.83       (65.80%)

n     

15.1

15.1

l              

1.99

1.99

f     

3.90

3.93

30 –

60 m

t

                     2.59                 (2)

                      2.52                (1)

v

                    11.58      (97.89%)

                    11.90         (100%)

n

11.5

11.3

l

2.61

2.65

f

4.44

4.49

60 –

80 m

t

                      1.69                (2)

                      1.72                (1)

v

                    11.83         (100%)

                    11.63      (97.73%)

n

7.3

7.7

l

2.74

2.60

f

4.32

4.47

80 –

100 m

t

1.78

1.70

v

                    11.24      (95.01%)

                    11.76      (98.82%)

n

7.05

7.1

l

2.84

2.82

f

3.96

4.17

 0 – 60 m

t

6.45

6.35

v

                      9.30      (78.61%)

                      9.45      (79.41%)

n

26.6

26.4

l

2.26

2.27

f

4.11

4.16

0 – 80 m

t

8.14

8.07

v

                      9.83      (83.09%)

                     9.91       (83.28%)

n

33.9

34.1

l

2.36

2.35

f

4.16

4.22

0 – 100 m

t

                     9.92                 (1)

                     9.77                 (1)

v

                    10.08      (85.21%)

                    10.24      (86.05%)

n

40.95

41.2

l

2.442

2.427

f

4.127

4.219

Note to Table 3.

t – running time (sec); v – running speed (m/seec); n – number of progressive runs; l – length of progressive run (m); f – frequency of progressive run (steps/sec).

In-between parenthesis, in the line "t" there is an indication of the place taken by the athlete by the end of the segment of the distance under study.

In-between parenthesis, in the line "v" there is an indication of the percent of speed gathered of the maximum (100%) one.

Therefore, the structure of the athlete's running technique in the two cases under study was stable.

30-60 m part of distance (distance run).

Unlike the preceding part of the distance (0-30 m), at the 30-60 m segment we observed some typical changes in the running technique of the athlete. If in the semi-final race at the segment under study he gathered 97.89% of the average maximum speed, in the final race he demonstrated maximum (100%) speed. The last, i.e. further increase in speed at the 30-60 m part of the distance, was achieved owing to the extension (by 4 cm) of the progressive run length and rise in the frequency of steps. There is an obvious increase in both components. It should be noted that the maximum speed attained at the 30-60 m segment in the final race enabled the sprinter to become the best at the segment, unlike the semi-final race, in which the athlete came second (comfortable advantage over the opponents creates the sense of self-confidence, which, in turn, allows leading an easy - ''playful" race at the preliminary competition laps, which we observed in the semi-final race).

Consequently, both speed components - length and frequency of progressive run, play a significant role in the performance improvement in the final race, which is typical for running at the 30-60 m part of the distance. The athlete's kinetic energy has increased by 5.6% from 11532.3 up to 12178.5 kg*m/sec.

60-80 m part of distance (distance run).

The third segment - distance run, like the preceding one, was covered faster in the semi-final race. It is to be noted that the differences between the running time in the semi-final and final races are insignificant (0.03 sec only), but at the same time, we should place particular emphasis upon the "action" of the progressive run length. In the main race of the World Cup the world record-breaker's progressive run decreased by 14 cm (compared with the 30-60 m segment), but surprisingly, its frequency remained practically at the same level. In other words, for 50 m (30-80 m) the athlete succeeded to keep the pace. However, the running speed in the final race, compared to the 30-60 m segment, slightly reduced (by 2.27%), while in the semi-final race this indicator reached the maximum (100%) level outright thanks to the consistent extension of the step length.

It follows that the length of progressive run becomes more of the determining factor affecting the athlete's performance.

80-100 m part of distance (finish).

In the final race, U. Bolt covered the final segment of the distance 0.08 sec faster, than at the preceding competition lap (high significance of the main race is obvious). In our opinion, the differences are mainly due to the fact that in the semi-final race the sprinter deliberately slowed down at the final meters of the race distance (7-8 meters before the finish) (the video analysis proved our assumptions) in view of his distinct advantage over the opponents and solution of the main task - to get into the final of the world championship. A bit relaxed running in the semi-final race, particularly at the finish line, which was demonstrated as a result of the deliberate slowdown, enabled the athlete to achieve the maximum length of progressive run (2.84 m) and slightly exceed (by 2 cm) the similar result achieved in the final race. And vice versa, some extension of the progressive run length in the final race had its effect on the decrease in speed at the finish line (the speed reduced) compared to the 60-80 m segment. Thus, if running speed at the 60-80 m part of the race distance, as previously mentioned, reduced by 2.27% of the average maximum values, at the 80-100 m segment it kept reducing, but at slower rates and equaled 1.18% of the maximum (100%).

When comparing the length of progressive run in two competition laps, it becomes apparent that a more significant increase in this kinematic indicator in the final race, compared with the 60-80 m segment (by 22 cm; in the semi-final race the increase equaled 10 cm), can also influence the conclusive result of the champion.

Therefore, once again, the variability of the length of progressive run affected the sports result to a greater extent.

Summing up, it can be stated that U. Bolt is able to control his running speed at the distance by adjusting the length of progressive run (we assume that length is the predominant factor in achievement of high sports results, unlike frequency, which is associated with the anthropometric characteristics of the athlete). This enables him to develop own running tactics depending on the level of physical fitness of his opponents and the tasks in hand at a particular competition lap. This could be possible only in case of his high readiness, which already creates reasonable opportunities for a firm victory.

The analysis of the kinematic indicators of technical skills of U. Bolt, where the distance was divided into two equal parts, revealed the following curious facts (Table 4).

When the 100 m distance run was analyzed by the four segments (0-30, 30-60, 60-80 and 80-100 m), in the semi-final and final races the average maximum speed was registered at the level of 11.83 and 11.90 m/sec, respectively (Table 3). However, the final race, reduced by the 50 m parts (segments), revealed the speed of 11.96 m/sec, that is, slightly higher (most probably, speed fluctuations may be observed when different parts of the race distance are analyzed, which will be proved hereafter). The authors of the article are sure that if U. Bolt had not deliberately "slowed down" at the finish line, his speed would have been higher than that presented in the table.

Table 4. kinematic indicators of technical skills of u. bolt in 100 m run

Parts

(segments)      of distance

Indicators

Competition lap.

Competitive performance

3th  semi-final race.

5th track. wind: + 0.1 m/sec. 11.08.2013. 19.21 hrs.

Final race.

6th track. wind: - 0.3 m/sec. 12.08.2013.  21.51 hrs.

0 –

50 m

t

                     5.66                 (2)

                     5.59                 (2)

v

                     8.83       (75.21%)

                     8.94       (74.75%)

n

22.95

23.05

l

2.18

2.17

f

4.05

4.12

50 –

100 m

t

                     4.26                 (1)

                     4.18                 (1)

v

                    11.74         (100%)

                    11.96        (100%)

n

18

18.15

l

2.78

2.75

f

4.23

4.34

Note to Table 4.

t – running time (sec); v – running speed (m/sec); n - number of progressive runs; l – length of progressive run (m); f – frequency of progressive run (steps/sec).

In-between parenthesis, in the line "t" there is an indication of the place taken by the athlete by the end of the part (segment) of the distance under study.

In-between parenthesis, in the line "v" there is an indication of the percent of speed gathered of the maximum (100%) one, attained by the athlete at the part (segment) of the 50-100 m distance.

However, the represented data are not enough to conduct a more in-depth study, as at particular sections of the race distance the relationship of the length, frequency of progressive run and running speed changed significantly. In this view, we measured these parameters at the shorter parts of the distance, which allowed building a different picture of the dynamics of these indicators while moving along the distance.

In that context, let us go into the details of run of female athletes, obtained while analyzing the speed components of the middle-distance race, which had already been registered by the fixings in the 100 m hurdles (5-7 hurdle cycle, 8.50 m spacing between the hurdles; 55.5-72.5 m segment).

In the semi-final race, at the 17.5 m segment (55.5 m to 72.5 m) the Jamaican gathered speed by means of increasing the length of progressive run (2.74 > 2.79 m), and at the next segment of the race distance he sustained speed owing to the insignificant rise in the frequency of progressive run (4.29 > 4.37 s/sec). This was due to the fact that, at the segment under study, the world record-breaker was slightly falling behind his weaker opponent (M. Rodgers, USA), and the increase in the pace enabled the Jamaican sprinter to breast the tape. The maximum speed in the finals, registered at the segment "55.5 – 64 m" equaled 12.31 m/sec, compared with the preceding segment (47-55.5 m), was provided by the frequency of progressive run (the length was maintained at the same level), and deceleration, observed at the other segment, was due to deterioration of both of the speed components (Table 5).

Table 5. kinematic indicators of technical skills of u. bolt in 100 m run

Parts

(segments)      of distance

Indicators

Competition lap.

Competitive performance

3th  semi-final race.

5th track. wind: + 0.1 m/sec. 11.08.2013. 19.21 hrs.

Final race.

6th track. wind: - 0.3 m/sec. 12.08.2013.  21.51 hrs.

47 –

55.5 m

(5-6 th h.c.)

t

0.73

0.71

v

11.64

11.97

l

2.74

2.74

f

4.25

4.37

55.5 –

64 m

(6-7 th h.c.)

t

0.71

0.69

v

11.97

12.31

l

2.79

2.74

f

4.29

4.49

64 –

72.5  m

(7-8th h.c.)

t

0.71

0.72

v

11.97

11.80

l

2.74

2.66

f

4.37

4.37

Note to Table 5.

t – running time (sec); v – running speed (m/sec); l – length of progressive run (m); f – frequency of progressive run (steps/sec); h. c. – hurdle cycles.

It is to be recalled here that, when setting up his world record in Berlin (2009, 9.58 sec), U. Bolt moved at the speed of 12.42 m/sec [1].

Table 6 presents the kinematic indicators of technical skills, and Figure 1 - the number of progressive runs depending on the sports result achieved during the competitions of 2008-2013.

Table 6. kinematic indicators of technical skills of u. bolt in 100 m run

Sl.No

Title of competition.

Place taken

Indicators

Running time,

sec

Running speed,

m/s

Number of progressive runs

Length of progressive run,

m

Frequency of progressive run, steps/sec

Startle response,

sec

1

XIV

World Cup

(Moscow, 2013).

1 place

Final race (wind: - 0.3 m/s)

9.77

10.24     

41.2

2.427

4.219

0.163

Semi-final race (wind: + 0.1 m/s)

9.92

10.08     

40.95

2.442

4.127

0.173

Preliminary race (wind: - 0.4 m/s)

10.07

9.93

40.4

2.48

4.00

0.155

2

XXX

Olympic Games

(London, 2012)

1 place

Final race (wind: + 1.5 m/s)

9.63

10.38

41

2.439

4.255

0.165

Semi-final race (wind: + 1.0 m/s)

9.87

10.13

40.1

2.493

4.063

0.180

Preliminary race (wind: + 0.4 m/s)

10.09

9.91

40

2.50

3.96

0.178

3

XIII

World Cup

 (Daegu, 2011)*

Semi-final race (wind: - 1.0 m/s )

10.05

9.95

40.5

2.469

4.029

0.164

Preliminary race (wind: - 0.7 m/s)

10.10

9.90

39.9

2.506

3.95

0.153

4

XII

World Cup

 (Berlin, 2009)

1 place

Final race (wind: + 0.9 m/s)

9.58

10.44

41

2.439

4.28

0.146

Semi-final race (wind: + 0.2 m/s )

9.89

10.11

40

2.50

4.04

0.135

Quarterfinal race (wind: + 0.1 m/s)

10.03

9.97

40.4

2.475

4.028

0.155

Preliminary race (wind: - 0.5 m/s)

10.20

9.80

40.85

2.447

4.004

0.144

5

XXIX

Olympic Games

(Beijing, 2008)

1 place

Final race (wind: 0 m/s)

9.69

10.32

41.1

2.433

4.241

0.165

Semi-final race (wind: - 0.1 m/s)

9.85

10.15

40

2.50

4.06

0.161

Quarterfinal race (wind: + 0.1 m/s)

9.92

10.08

39.9

2.506

4.02

0.165

Preliminary race (wind: - 0.2 m/s)

6

World record

(New York, 2008)

1 place

Final race (wind: + 1.7 m/s)

9.72

10.29

41.3

2.42

4.25

--
                 

Note to Table 6.

The bolded sports results are the world records.

* At the 2011 World Championship U. Bolt violated the rules of the competition (he broke away in the finals), due to which he was excluded from participation in the final race.   

Fig. 1. Number of progressive runs of U. Bolt depending on the sports result in the 100 m run (the results depicted were obtained during the final races in various large-scale competitions and the world record – 9.72 sec)

Conclusions. The data stipulated in the given paper suggest that when running an athlete has a chance to (or can) manage kinematic characteristics that determine speed based on the situation in a given round of competition (video analysis of athlete’s running indicates that he is moving confidently along the distance that confirms his superiority over opponents).

It can be stated that the progressive run length and frequency are largely the leading (or determining) factors of better performance in the 100 m distance run of the world champion 2013 U. Bolt. They in the proper ratio affect the performance of a particular athlete in the 100 m distance run. However, thanks to the athlete’s anthropometric characteristics (according to IAAF his body length is 195 cm) one can focus on the step length.

Unlike U. Bolt, another prominent female athlete from Jamaica, world champion (2013) and Olympic champion (2012) in 100 m run, Shelly-Ann Fraser-Pryce achieves high results owing to a different determining factor - frequency of progressive run [5]. This speed component is mostly typical for athletes specializing in sprint who have the corresponding anthropometric characteristics (according to IAAF, the athlete's body length is 1.60 m).

Sprinters with different anthropometric characteristics normally gather high speed in different ways. Tall athletes have a longer running step and lower frequency of movements. And conversely, not so tall athletes strive for attainment of the maximum speed mainly by increasing the frequency of progressive run.

The primary purpose of sprint race is to maximize horizontal speed. In some athletes running speed can be defined by the length of their progressive run, in others - by its frequency. Based on the submitted data, U. Bolt and his coach lay emphasis on the length and, partially, frequency of progressive run.

Was that U. Bolt phenomenon or a short-duration product? The athlete's performance in the period from 2008 to the present day has proved his uniqueness and capability to always come first. As has been demonstrated by this Jamaican athlete's competitive activity, the high level of special physical fitness enables him to start leading several meters before the finish line, both in the 100 m and 200 m distance run.

Obviously, 2017 will be the year of termination of the athlete's professional career, of which he said time and again (the XVI World Championship in Athletics, which is scheduled to be held in London, will become the biggest event of the year). At the XXXI Olympic Games in Rio de Janeiro (2016) U. Bolt will yet again try to prove not just own phenomenality, but also the consistency of the Jamaican school (not only him) of sprint race in the last few years of the new age. The athlete is sure, as he announced after winning the London Olympics, that in the history of athletics he has become the legend of sprint.

Which is of prime interest for athletics enthusiasts - U. Bolt's new records or repetition of his successes of 2008 and 2012? Most probably, both are.

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Corresponding author: prorector@mail.ru