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Sport Sci Health (2008) 4:51–58 DOI 10.1007/s11332-008-0067-1
ORIGINAL ARTICLE
Combined endurance and resistance circuit training in highly trained/top-level female race walkers: a case report Antonio La Torre · Gianluca Vernillo · Pierluigi Fiorella · Clara Mauri · Luca Agnello
Received: 23 October 2008 / Accepted: 20 November 2008 © Springer-Verlag 2008
Abstract Race walking can be considered as a long-distance performance and it can be described as the technical and athletic expression of fast walking. The physiological determinants of these performances have been well documented; moreover, several recent studies demonstrated that concurrent strength and endurance training can improve performance in endurance athletes. Thus, the purpose of this report was to monitor the adaptations of a combined strength, performed by circuit resistance training (CRT), and endurance programme in two top level female race walkers. The subjects were examined before and after 12 weeks of CRT and endurance training and performed an incremental field test to determine maximum oxygen uptake (V˙O2max), running economy (RE) and lactate threshold (LT). The results
A. La Torre · G. Vernillo Faculty of Exercise Sciences University of Milan Milan, Italy P.L. Fiorella · C. Mauri Medicine and Sport Science Institute Italian National Olympic Committee Rome, Italy L. Agnello Department of Basic and Applied Medical Sciences University “G. d’Annunzio” Chieti-Pescara, Italy A. La Torre (쾷) Istituto di Esercizio Fisico, Salute e Attività Sportiva (IEFSAS) Via Giuseppe Colombo 71 20133 Milan, Italy e-mail:
[email protected]
showed that 12 weeks of combined CRT and endurance ˙ O2max programme did not correspond to an alteration in V and RE, while improvements in LT and 5-km performance were seen. Key words Race walking · Explosive strength · Circuit resistance training
Introduction The general assumption for walking said that process of locomotion in which the moving body is supported by first one leg and then the other. When the moving body passes over the supporting leg, the other leg swings forward in preparation for its next support phase. One foot or the other is always on the ground, and during that period, when the support of the body is transferred from the trailing to the leading leg, there is a brief period when both feet are on the ground [1]. Race walking can be described as the technical and athletic expression of fast walking; competition walkers attain speeds about double the maximum walking speed of an average person with a less step increase in energy expenditure, maybe due to two factors: (i) less mechanical work done to move forwards and/or (ii) the efficiency of positive work [2, 3]. Moreover, race walking has some other technical aspects, ruled by International Association of Athletics Federations (IAAF) rule 230, which increase the difficulty of locomotion: (i) loss of contact; and (ii) bent knee. The difference between common walking and race walking and the limits to race walking performance derive directly from these technical and ruling aspects, thus, even endowed with extraordinary physiological qualities,
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a race walker without a strong technique may never achieve significant results. The physiological determinants of long-distance running performance, as race walking, have been well documented. Traditionally, it has been suggested that these factors are: (i) maximum oxygen uptake (V˙O 2max) [4–6]; (ii) lactate threshold (LT) [6, 7]; (iii) running economy (RE) [4, 6, 8, 9]; and (iv) percent of maximum oxygen uptake (%V˙O2max) [4]. These determinants explain >70% of the between-subject variance in long-distance running performance [10]. Factors related to muscular power, such as neuromuscular and anaerobic aspects, have been recently added. Noakes [11] and Green and Patla [12] have suggested that V˙O2max and endurance performance may be limited not only by central factors related to O2 uptake (V˙O2max) but also by so-called ‘‘muscle power’’ factors affected by an interaction of neuromuscular and anaerobic characteristics [13]. These factors can limit, and even can be the precursors to, endurance performance [14–16]. These physiological determinants can be considered as intrinsic factors [17], such as genetic [18–21] and psychic characteristics [22], and extrinsic factors [17], such as lifestyle and daily activity [17, 23, 24], training [23, 25] and environment conditions [26, 27]. It has been suggested that simultaneous training for both strength and endurance may be associated with limited strength development in endurance athletes [11, 26, 27] without changes in the endurance determinants. Whereas, explosive and plyometric training programmes, in endurance athletes, does not behave the development of the endurance determinants [13, 28, 29]. Moreover, a different kind of strength training, circuit resistance training (CRT), deemphasises the brief intervals of heavy, local muscle overload in standard resistance training, providing a more general conditioning that improves body composition, muscular resistance and endurance, and cardiovascular fitness [43, 44]. Although the effect of combined strength and endurance training on physical performance has become a popular research topic in the last decade [33], a few studies have analysed the impact of resistance training on the endurance disciplines and have reported that: (i) plyometric training improves RE and ultimately distancerunning performance, although the exact mechanism by which this occurs remains unclear [13, 34, 35]; (ii) CRT sets are quantitatively similar to traditional strength training sets, but the cardiovascular load is substantially greater. CRT may be an effective training strategy for the promotion of both strength and cardiovascular adaptations and alone induced strength and power improvements that were significantly greater than when resis-
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tance and endurance training were combined [45, 46]. Moreover, in the literature, there are no studies concerning these aspects in race walking. Thus, the aim of this report was to monitor the adaptations of a combined strength, performed by CRT, and endurance programmes in two highly trained female race walkers.
Materials and methods
Subjects Two highly trained females with 11±1 years’ experience, who competed in the IAAF Race Walking Challenge and World Race Walking Cup 2008, were analysed in the present study. The averages of the subjects’ physical and physiological characteristics before and after the training period are presented in Table 1. All participants were fully informed about the aims of the study, the procedures and the training, and gave their voluntary consent before participation. The experimental procedures were in agreement with the Declaration of Helsinki on human experimentation.
Training project The experimental training period lasted for 12 weeks. The total training volume was 1200±30 h/year but 10% of training hours were replaced by CRT. CRT sessions lasted for 20–30 min at a frequency of 3 times per week. The programme included eight different exercises (Fig. 1) without additional weight or with low loads but high or maximal movement velocities (64–160 contractions/training session and 8–12 repetitions/set). The load of the exercises ranged between 0 and 40% of the one-repetition maximum.
Table 1 Physical characteristics and training background of the experimental group Variable
Experimental group Before
Age (years) Height (cm) Body weight (kg) BMI Training background Training (h/year) Circuit training times/week Values are means±SD
23 171.5±0.5 53.4±3.6 18.1±1.4 11±1 1200±30 2
After
52±4.1 17.7±1.5
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Fig. 1 CRT programme
100 % strenght 90 %
aerobic endurance 95% of the LT
80 %
above LT
70 % 60 % 50 % 40 % 30 % 20 % 10 % 0%
Fig. 2 Relative volumes (%) of different training during course of 12-week simultaneous CRT and aerobic endurance training
In detail, workload intensities ranged from 20% to 75% of the athletes’ limits, below (75%) or above (20%) the individual lactate threshold (LT), for example 3×1000 or 1×2000 race walking with 2 min rest between repetitions (Fig. 2).
Measurements Highly trained race walkers were examined before and after 12 weeks of training. The tests were performed in February and then in April before the competition peri-
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od. All tests were performed on a synthetic 400-m track in a climate of 8–16°C without wind. Two testing sessions were conducted. In the first one, the subjects performed an incremental field test to determine maximal oxygen uptake (V˙O2max) where the speed was increased by 1 km/h each minute. Two days later, in the second session, RE was measured as steady-state sub-maximal oxygen uptake during incremental steps of eight minutes at constant velocity with 30 sec of recovery. Throughout the incremental test, the subjects adopted the required velocity by use of an audio-visual system. This system included guide marks set at 20-m intervals along the track and audio signals to determine the speed needed to cover the intervals. A peripheral lactate increase over velocity corresponding to 4 mmol·L–1 during an incremental exercise test can be adopted as an evaluation criterion of the anaer˙ CO2 and V˙E were measured obic threshold [47]. V˙O2, V throughout the test using a telemetric system (K4b2, Cosmed, Rome, Italy) [48, 49] and heart rate (HR) was monitored continuously for all sessions (Polar Electro, Kempele, Finland). Expired gases were measured breathby-breath and averaged every 5 s. Before each test, the O2 analysis system was calibrated using ambient air (20.9% O2 and 0.04% CO2) and calibration gas (16% O2 and 5% CO2). The calibration of the turbine flow-meter of the analyser was performed with a 3-l syringe. During the exercise test, a capillary blood sample was obtained from the ear lobe and analysed for blood lactate concentration (Lactate Pro LT, Arkay Inc., Kyoto, Japan) [50]. The samples were taken immediately after the warmup and after each velocity at the end of the incremental test.
Results The V˙O2max before and after 12 weeks of CRT was 3209±436 vs. 2882±651 ml·kg–1·min–1, respectively (Fig. 3). Before and after the 12 week programme, immediately after the end of the V˙O2max test, mean blood lactate concentration was 8.75±1.06 mmol·L–1 and 8.85±0.64 mmol·L–1, respectively (Fig. 4). The LT at velocity corresponding to 4 mmol·L–1 was, before and after the protocol, 12.4±0.2 km·h–1 and 12.9±0.1 km·h–1, respectively. There were no changes in RE (Fig. 5). The maximal heart rate was, before and after training, 189±8 vs. 190±7 beats·min–1, respectively (Fig. 6).
Discussion The main purpose of the present report was to test the effects of a CRT on race walking performance. As showed by Paavolainen et al. [13], the combined explosive strength and endurance training improved force, running velocity, RE and 5-km running performance in well ˙ O2max, trained endurance athletes without any changes in V according to what we find in the present report, where the aerobic capacity of the subjects does not improve after 12 weeks of combined CRT and endurance training. Moreover, in the literature there are discordant data about the possible changes of the LT after concomitant endurance and strength training. Several studies have shown no changes in LT after the training protocol [13, 40], while Marcinik et al. found an improvement in the subjects’ LT [42]. Along with Jung [41], we hypothe-
4000
pre post
VO2max (mL·kg-1·min-1)
3500 3000 2500 2000 1500 1000 500 0 12.00
13.00
14.00
Speed (km·h-1) Fig. 3 V˙O2max and speed relationship before and after 12 weeks of CRT. Values are means±SD
15.00
16.00
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12.00
pre
Blood lactate concentration (mmol·L-1)
post 10.00
8.00
6.00
4.00
2.00
0.00 11.00
12.00
13.00
Speed
14.00
15.00
(km·h-1)
Fig. 4 Blood lactate curve before and after 12 weeks of CRT. Values are means±SD
300.0
pre post
RWE (mL·kg-1·min-1)
250.0
200.0
150.0
100.0
50.0
0.0 11.00
12.00
13.00
Speed (km·h-1)
Fig. 5 RWE and speed relationship before and after the 12 weeks of CRT. Values are means±SD
sise that after CRT the muscle fibres are capable of producing more absolute force, working at a lower percentage of maximum strength during endurance activity compared with pre-training. This decrease in effort may have resulted in a decrease in anaerobic energy production, resulting in a decrease in blood lactate concentration [42]. Regarding the RE, but in our opinion it would be better to refer to race walking economy (RWE), in contrast to the literature [35, 39], we found a worsening. This may
be due to the intrinsic factors of race walking, as the technical and biomechanical aspects may require a longer period of adaptation after the training. In conclusion, we have shown that 12 weeks of a combined circuit training and endurance programme improve the 5-km performances but there were no corresponding ˙ O2max. alterations in V Further research is needed to establish whether such race walking improvements derive from an increased stride length or stride frequency or both and, as suggest-
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Sport Sci Health (2008) 4:51–58 210
pre post
Heart rate (beats·min-1)
200
190
180
170
160
150 11.00
12.00
13.00
Speed
14.00
15.00
(km·h-1)
Fig. 6 Heart rate and speed relationship before and after 12 weeks of CRT. Values are means±SD
0.24.46 0.24.29
5 km performance (h·mm·ss)
0.24.12 0.23.54 0.23.37 0.23.20 0.23.02 0.22.45 0.22.28 0.22.11 2004
2005
2006
2007
2008
2009
Years Fig. 7 Average of the 5-km performance from 2005 to 2008
ed by Nummela et al. [51], if these improvements might be due to enhancement in ground contact times. In our opinion, this improvement might enhance 5-km performance (Fig. 7) after 12 weeks of training. Thus, further research is needed to establish if this improvement is due to combined CRT and endurance training. According to Häkkinen et al. [52] the present data do not support the concept of the ‘‘interference effect’’ in strength
development and muscle hypertrophy when strength training is performed concurrently with endurance training. Instead, in our opinion, explosive strength development in the subjects seems to be due to an improvement in the rapid neural activation of the trained muscles. In addition, according to Nummela et al. [51], the results of the present study support the idea that distance runners’ performance is related to neuromuscular capacity to produce force.
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Practical applications Collectively, these findings add further support to the interpretation of the results of the training study in which combined endurance and CRT improved skeletal muscle force–velocity characteristics, such as, maybe, motor unit recruitment and synchronisation. Further research is needed to determine whether more intense or more prolonged circuit training improves RE and the performance of highly trained race walkers. Acknowledgements The authors wish to thank the athletes and coach Vincenzo Fiorillo for his assistance in data collection and technical support. Conflict of interest statement The authors declare that they have no conflict of interest related to the publication of this article.
References 1. Rose J, Gamble JG (2006) Human walking. Lippincott Williams & Wilkins, Philadelphia, USA, p 2 2. Cavagna GA, Franzetti P (1981) Mechanics of competition walking. J Physiol 315:243–251 3. Menier DR, Pugh LGCE (1968) The relation of oxygen intake and velocity of walking and running, in competition walkers. J Physiol 197:717–721 4. Basset DR Jr, Howley ET (2000) Limiting factors for maximum oxygen uptake and determinants of endurance performance. Med Sci Sports Exerc 32:70–84 5. Billat VL, Demarle A, Slawinski J et al (2001) Physical and training characteristics of top-class marathon runners. Med Sci Sports Exerc 33:2089–2097 6. Noakes TD, Myburgh KH, Schall R (1990) Peak treadmill running ˙ O2max test predicts running performance. J velocity during the V Sports Sci 8:35–45 7. Tanaka K, Matsuura Y (1984) Marathon performance, anaerobic threshold and onset of blood lactate accumulation. J Appl Physiol 57:640–643 8. Conley DL, Krahenbuhl GS (1980) Running economy and distance running performance of highly trained athletes. Med Sci Sports Exerc 12:357–360 9. Morgan DW, Baldini FD, Martin PE, Kohrt WM (1989) Ten kilo˙ O2max among wellmetres performance and predicted velocity at V trained male runners. Med Sci Sports Exerc 21:79–83 10. di Prampero PE, Atchou G, Brückner JC, Moia C (1986) The energetics of endurance running. Eur J Appl Physiol 55:259–266 11. Noakes TD (1988) Implications of exercise testing for prediction of athletic performance: a contemporary perspective. Med Sci Sports Exerc 20:319–330 12. Green HJ, Patla AE (1992) Maximal aerobic power: neuromuscular and metabolic considerations. Med Sci Sports Exerc 24:38–46 13. Paavolainen L, Häkkinen K, Hämäläinen I et al (1999) Explosive strength training improves 5-km running time by improving running economy and muscle power. J Appl Physiol 86:1527–1533 14. Houmard JA, Costill DL, Mitchell JB et al (1991) The role of anaerobic ability in middle distance running performance. Eur J Appl Physiol 62:40–43
57 15. Noakes TD (2000) Physiological models to understand exercise fatigue and the adaptations that predict or enhance athletic performance. Scand J Med Sci Sports 10:123–145 16. Sinett AM, Berg K, Latin RW, Noble JM (2001) The relationship between field tests of anaerobic power and 10-km run performance. J Strength Cond Res 15:405–412 17. La Torre A, Impellizzeri FM, Dotti A, Arcelli E (2005) Do Caucasian athletes need to resign themselves to African nomination in long and middle distance running? New Studies in Athletics 20:39–49 18. Bouchard C, Rankinen T (2001) Individual differences in response to regular physical activity. Med Sci Sports Exerc 33[Suppl]: S446–451; discussion S452–453 19. Larsen HB (2003) Kenyan dominance in distance running. Comp Biochem Physiol A Mol Integr Physiol 136:161–170 20. Scott RA, Wilson RH, Goodwin WH et al (2005) Mitochondrial DNA lineages of elite Ethiopian athletes. Comp Biochem Physiol Biochem Mol Biol 140:497–503 21. Scott RA, Moran C, Wilson RH et al (2005) No association between angiotensin converting enzyme (ACE) gene variation and endurance athlete status in Kenyans. Comp Biochem Physiol A Mol Integr Physiol 14:169–175 22. Kayser B (2003) Exercise starts and ends in the brain. Eur J Appl Physiol 90:411–419 23. Saltin B, Kim CK, Terrados N et al (1995) Morphology, enzyme activities and buffer capacity in leg muscles of Kenyan and Scandinavian runners. Scand J Med Sci Sports 5:222–230 24. Scott RA, Georgiades E, Wilson RH et al (2003) Demographic characteristics of elite Ethipian endurance runners. Med Sci Sports Exerc 35:1727–1732 25. Coetzer P, Noakes TD, Sanders B et al (1993) Superior fatigue resistance of elite black South African distance runners. J Appl Physiol 75:1822–1827 26. Saunders PU, Telford RD, Pyne DB et al (2004) Improved running economy in elite runners after 20 days of simulated moderate-altitude exposure. J Appl Physiol 96:931–937 27. Schmidt W (2002) Effects of intermittent exposure to high altitude on blood volume and erythropoietic activity. High Alt Med Biol 3:167–176 28. Hunter G, Demment R, Miller D (1987) Development of strength and maximum oxygen uptake during simultaneous training for strength and endurance. J Sports Med Phys Fit 27:269–275 29. Paavolainen L, Häkkinen K, Rusko H (1991) Effects of explosive type strength training on physical performance characteristics in cross-country skiers. Eur J Appl Physiol 62:251–255 30. Dudley GA, Djamilj R (1985) Incompatibility of endurance and strength-training modes of exercise. J Appl Physiol 59:1446–1451 31. Hickson RC (1980) Interference of strength development by simultaneously training for strength and endurance. Eur J Appl Physiol 215:255–263 32. Hickson, RC, Rosenkoetter AM, Brown MM (1980) Strength training effects on aerobic power and short-term endurance. Med Sci Sports Exerc 12:336–339 33. Hoff J, Gran A, Helgerud J (2002) Maximal strength training improves aerobic endurance performance. Scand J Med Sci Sports 12:288–295 34. Johnston RE, Quinn TJ, Kertzer R, Vroman NB (1997) Strength training in female distance runners: impact on running economy. J Strength Cond Res 11:224–229 35. Spurrs RW, Murphy AJ, Watsford ML (2003) The effect of plyometric training on distance running performance Eur J Appl Physiol 89:1–7 36. Mikkola J, Rusko H, Nummela A et al (2007) Concurrent endurance and explosive type strength training increases activation and fast force production of leg extensor muscles in endurance athletes. J Strength Cond Res 21:613–620
051_058_LaTorre:Sport
10-02-2009
10:41
Pagina 58
58 37. Mikkola J, Rusko H, Nummela A et al (2007) Concurrent endurance and explosive type strength training increases improves neuromuscular and anaerobic characteristics in young distance runners. Int J Sport Med; 28:602–611 38. Saunders PU, Telford RD, Pyne DB et al (2006) Short-term plyometric training improve running economy in highly trained middle and long distance runners. J Strength Cond Res 20:947–954 39. Turner AM, Owings M, Schwane JA (2003) Improvement in running economy after 6 weeks of plyometric training. J Strength Cond Res 17:60–67 40. Bishop D, Jenkins DG (1999) The effects of strength training on endurance performance and muscle characteristics. Med Sci Sports Exerc 31:886–891 41. Jung AP (2003) The impact of resistance training on distance running performance. Sports Med 33:539–552 42. Marcinik EJ, Potts J, Schlabach G et al (1991) Effects of strength training on lactate threshold and endurance performance. Med Sci Sports Exerc 23:739–743 43. Ballor DL, Becque MD, Katch VL (1987) Metabolic response during hydraulic resistance exercise. Med Sci Sports Exerc 19:363–367 44. Katch FI, Freedson PS, Jones CA (1985) Evaluation of acute cardiorespiratory responses to hydraulic resistance exercise. Med Sci Sports Exerc 17:168–173 45. Chtara M, Chaouachi A, Levin GT et al (2008) Effect of concurrent endurance and circuit resistance training sequence on mus-
Sport Sci Health (2008) 4:51–58
46.
47.
48.
49.
50.
51.
52.
cular strength and power development. J Strength Cond Res 22:1037–1045 Alcaraz PE, Sánchez-Lorente J, Blazevich AJ (2008) Physical performance and cardiovascular responses to an acute bout of heavy resistance circuit training versus traditional strength training. J Strength Cond Res 22:667–671 Mader A, Liesen H, Heck H et al (1976) Zur Beutreilung der sportspezifischen Ausdauerleistungsfähigkeit im Labor. Sportarzt Sportmed 27:80–88/109–112 Einsenmann JC, Brisko N, Shadrik D, Welsh S (2003) Comparative analysis of the Cosmed Quark b2 and K4b2 gas analysis systems during submaximal exercise. J Sports Med Phys Fitness 43:150–155 McLaughlin JE, King GA, Howley ET et al (2001) Validation of the COSMED K4 b2 portable metabolic system. Int J Sports Med 22:280–284 Pyne DB, Boston T, Martin DT, Logan A (2000) Evaluation of the Lactate Pro blood lactate analyser. Eur J Appl Physiol 82:112–116 Nummela AT, Paavolainen LM, Sharwood KA et al (2006) Neuromuscular factors determining 5 km running performance and running economy in well-trained athletes. Eur J Appl Physiol 97:1–8 Häkkinen K, Alen M, Kraemer WJ et al (2003) Neuromuscular adaptations during concurrent strength and endurance training versus strength training. Eur J Appl Physiol 89:42–52