Are the Beneficial Effects of Ischemic Preconditioning ...

IJSM/4763/17.4.2015/MPS

Are the Beneficial Effects of Ischemic Preconditioning on Performance Partly a Placebo Effect?

Authors

M. Marocolo1, 2, G. R. da Mota1, V. Pelegrini1, H. -J. Appell Coriolano2

Affiliations

1

Key words ▶ blood flow occlusion ● ▶ swimming ● ▶ skeletal muscle ●

Human Performance and Sport Research Group, Department of Sport Sciences, Federal University of Triângulo Mineiro, Uberaba, Brazil 2 Physiology & Anatomy, German Sport University, Cologne, Germany

Abstract

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The acute effect of ischemic preconditioning (IPC) on the maximal performance in the 100-m freestyle event was studied in recreational swimmers. 15 swimmers (21.0 ± 3.2 years) participated in a random crossover model on 3 different days (control [CON], IPC or SHAM), separated by 3–5 days. IPC consisted of 4 cycles of 5-min occlusion (220 mmHg)/5-min reperfusion in each arm, and the SHAM protocol was similar to IPC but with only 20 mmHg during the occlusion phase. The subjects were informed that both maneuvers

Introduction

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accepted after revision March 24, 2015 Bibliography DOI http://dx.doi.org/ 10.1055/s-0035-1549857 Published online: 2015 Int J Sports Med © Georg Thieme Verlag KG Stuttgart · New York ISSN 0172-4622 Correspondence Prof. Moacir Marocolo Department of Sport Sciences Federal University of Triângulo Mineiro Av Tutunas 490 38061-500 Uberaba Brazil Tel.: + 55/34/33185 067 Fax: + 55/34/33185 067 [email protected]

Since it had been demonstrated that ischemic preconditioning (IPC) ensured greater protection to myocardial cells against events of restricted blood flow [19], some studies have sought to test whether IPC may improve recovery [2] or sports performance [6, 7, 15]. Libonati et al. [17] proposed the use of IPC in physical exercises and showed increases in muscle force output. Other studies positively tested submaximal [4] and maximal incremental exercises on a cycle ergometer [6, 7], submaximal and maximal swim tests [15], graded maximal treadmill running test [1], in land based maximal running sprint [11], and maximal power tests on a cycle ergometer [20]. Besides these positive effects of IPC, this maneuver was not associated with improved performance in some studies that measured maximal peak power [16, 20] or maximal effort sprints [10] on a cycle ergometer, sprint run tests [11] and muscle recovery in resistance exercise [5]. It may be argued that the effects of IPC depend on the type of performance or are more beneficial for some sports disciplines but not for others. Due to the lack in unequivocal results, more

(IPC and SHAM) would improve their performance. After IPC, CON or SHAM, the volunteers performed a maximal 100-m time trial. IPC improved performance (p = 0.036) compared to CON. SHAM performance was only better than CON (p = 0.059) as a tendency but did not differ from IPC performance. The individual response of the subjects to the different maneuvers was very heterogeneous. We conclude that IPC may improve performance in recreational swimmers, but this improvement could mainly be a placebo effect.

experimental protocols should be desirable to enlarge the understanding of IPC effects on sports performance. Jean-St.-Michel and colleagues [15] studied IPC in elite swimmers and clearly concluded that this preconditioning improved performance. However, when thoroughly analyzing those data, it appeared that a low-pressure IPC (well below diastolic blood pressure) also had some effects. Therefore one might suspect some kind of placebo effects from this intervention. As a result, the aim of this study was to verify whether IPC can acutely improve performance on a maximal swimming test in recreational swimmers, in comparison to a sham maneuver. We hypothesized that arm IPC would increase performance as assessed through a 100-m freestyle time trial.

Methods

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15 amateur swimmers participated in this study ▶ Table 1). All participants were healthy and ( ● competitive swimmers at the recreational level. Exclusion criteria included: 1) less than 6 months of competitive training; 2) smoking history during the last 3 months; 3) presence of any cardio-

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Training & Testing

vascular disease; 4) use of creatine supplementation; 5) use of anabolic steroids or 6) recent musculoskeletal injury. This study was approved by the local institutional Ethical Committee for Human Experiments and was performed in accordance with ethical standards in sport and exercise science research [12]. Each subject was tested 3 times, with at least 3 and no more than 5 days between the evaluations. The volunteers were told that both protocols [IPC and SHAM] could improve performance. The first visit was used for familiarization with the test procedure. For the second, third and fourth visit, a randomized crossover assignment (CON, IPC or SHAM followed by 5-min warm-up and 100-m sprint test) was adopted. The organization of the experimental design is presented in ● ▶ Fig. 1.

out in the afternoon (15:00–17:00 h). Similar strong verbal encouragement was given to all subjects to motivate them throughout each test.

Ischemic preconditioning maneuver

Results

100-m time trial performance test

The 100-m performance test (front crawl style) was conducted in a 25-m swimming pool (26–28 °C). Each volunteer carried out the test individually in the middle lane of the swimming pool. Each trial started with the swimmer in the water, pushing off from the wall to exclude or at least minimize differences among start techniques. The time of each sprint was measured by 3 judges using manual chronometers (SEIKO S141-300, Japan). The mean time was considered. All time trial tests were carried

Table 1 Anthropometric data and performance characteristics. Parameters

Values (mean ± SD)

height (cm) weight (kg) age (years) body fat ( %) best time crawl 100 m (sec) Training History years days per week

3–5 days

CON, IPC or SHAM

randomized and separated by 3–5 days

179.2 ± 7.1 70.9 ± 9.6 21.1 ± 3.7 7.4 ± 2.6 68.9 ± 4.1 2.1 ± 0.9 3.2 ± 0.7

Anthropometric measures and procedures of familiarization

The Shapiro-Wilk test was applied to verify the normality of the data. For intergroup analysis, one-way analysis of variance (ANOVA) for repeated measurements was conducted, which was followed by a post-hoc Tukey’s test. Additionally, the effect size was calculated. The significance level was set at 0.05 and the software used for data analysis was GraphPad® (Prism 5.0, San Diego, CA, USA).

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All volunteers (n = 15) attended all protocols (CON, IPC and SHAM). ● ▶ Fig. 2 shows that IPC improved performance (p = 0.036) in comparison to the CON situation, by 1.46 % (considering the mean), which equals a reduction of 1.1 s in the 100-m time. The effect size (0.01) was trivial. 12 out of 15 participants (80 % of sample) improved their performance after IPC. However, 10 of 15 (67 %) volunteers reduced their 100-m time after the SHAM maneuver compared to CON. Yet for the whole group this improvement (0.7 s) was not significant, although it was a strong tendency (p = 0.059). There was no significant difference between IPC and SHAM (p = 0.76). When analyzing the swim times under the different conditions for each individual, the picture emerged that the subjects did not respond to the IPC or SHAM maneuver in a consistent manner. It appears that some improved their swim time for both conditions, while others per▶ Fig. 3). formed weaker ( ●

Discussion

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Our main finding was that IPC of the arm muscles could improve performance in recreational swimmers, supporting our initial hypothesis. Thus it appears feasible to obtain benefits from IPC when used before an exercise test or competition. Our results are similar to other studies that acutely used IPC to improve performance and described increases in maximal cycle

80 Time to 100-m swimming (s)

IPC consisted of 4 cycles of 5-min occlusion (220 mmHg)/5-min reperfusion (no pressure) in each arm (total duration 40 min), using a pneumatic tourniquet (ITS-MC, 28–100, Novo Hamburgo, Brazil) administered at the proximal part of the arms below the axilla. The occlusion and reperfusion phases were conducted alternately between the arms, with subjects remaining seated. In the SHAM protocol, an external pressure of 20 mmHg was administered, as proposed in previous studies [15, 20]. For the control tests, the volunteers stayed 40 min in rest to mimic the same time spent in the others 2 situations.

Statistical analysis

*

70 60 50 40

5-min

5-min warm-up

5-min

100-m time trial

Fig. 1 Experimental design of the study.


CON

IPC

SHAM

Fig. 2 Swim times over 100-m crawl (mean and SD) under control, IPC and SHAM conditions, * p = 0.036 compared to control.


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Training & Testing

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compared to muscles of the shoulder girdle [14]. This muscle, which is active during the swim cycle [22], certainly becomes ischemic with the IPC protocol. However, other important muscles (e. g., latissimus dorsi and pectoralis) responsible for about 70 % of arm propulsive forces [3] are not affected. Therefore upper extremity IPC protocols in swimming should be reconsidered, and this potential methodological flaw may further support our assumption regarding a placebo effect.

65

Conclusion

100-m time trial (s)

80

75

▼ CON

IPC

SHAM

Fig. 3 Individual swimmers’ 100-m time after each maneuver: control, IPC and SHAM.

ergometer test time [6], in VO2max [7] and in peak power for sprints [21], as well as improvement in swim times [15]. Although some studies had shown no or even unfavorable effects after IPC [2, 6, 20, 23], it seems that these negative effects may be mainly provoked in shorter exercises [2, 20], while IPC may be more effective in longer activities (with more aerobic contribution). On the other hand, a recent report [23] failed to show improvements in 5 000-m self-paced running after IPC. 12 of the 15 volunteers who participated in this study showed improvement in the 100-m time trial. This represents 80 % of our sample, indicating that mean improvements in performance of the group was also present in the majority of individuals. However, similar results were found for SHAM (without significant differences), where 10 of the volunteers also reduced their 100-m time. Considering that swimming is an individual sport, the individual responses of each person to the IPC protocol ▶ Fig. 3). Nevertheless, it seems that IPC should be highlighted ( ● in general provides positive influences on performance, using sufficient pressure to promote occlusion. The present experimental design is basically consistent with those used in other studies [1, 6, 7, 11, 15]. All of these studies applied a randomized and crossover design, comparing IPC and a control intervention, either untreated controls or sham controls with a low-pressure tourniquet. What is unique in the present experiments and sets apart our results from those of others is the fact that all participants were informed that they could expect beneficial effects from both maneuvers, IPC and SHAM. Assuming that the outcome of performance tests also depends on the subjects’ motivation, this information could have stimulated some subjects to make maximal efforts. This may, on the other hand, explain why the effects of the interventions were not uniform across the group of subjects and why some individual improvements in swimming time occurred after SHAM intervention. Another point to be considered when administering IPC at the upper extremity in swimmers [15] is the potential effectiveness of occluding the blood supply to propulsive muscles of the upper extremity. The contribution of propulsive force in crawl swimming is different for arms and legs, being almost 90 % for the upper extremities [8, 13, 18]. Among the muscles responsible for the arm movement, the triceps brachii muscle has been estimated to contribute about 30–40 % in the push phase of the crawl swimming cycle [9], and it showed considerable fatigue

The present study, at first glance, supported the concept of the beneficial effects of IPC on performance. However, at least in recreational athletes such as the subjects of this study, any intervention that might lead athletes to expect improvements in performance could possibly represent a placebo effect.

Acknowledgements

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This study has received financial support by CAPES No. 1142/143, which is highly appreciated by the authors.

Conflict of interest: No conflict of interest declared. References

1 Bailey TG, Jones H, Gregson W, Atkinson G, Cable NT, Thijssen DH. Effect of ischemic preconditioning on lactate accumulation and running performance. Med Sci Sports Exerc 2012; 44: 2084–2089 2 Beaven CM, Cook CJ, Kilduff L, Drawer S, Gill N. Intermittent lower-limb occlusion enhances recovery after strenuous exercise. Appl Physiol Nutr Metab 2012; 37: 1132–1139 3 Chollet D, Seifert L, Leblanc H, Boulesteix L, Carter M. Evaluation of arm-leg coordination in flat breaststroke. Int J Sports Med 2004; 25: 486–495 4 Clevidence MW, Mowery RE, Kushnick MR. The effects of ischemic preconditioning on aerobic and anaerobic variables associated with submaximal cycling performance. Eur J Appl Physiol 2012; 112: 3649–3654 5 Cochrane DJ, Booker HR, Mundel T, Barnes MJ. Does intermittent pneumatic leg compression enhance muscle recovery after strenuous eccentric exercise? Int J Sports Med 2013; 34: 969–974 6 Crisafulli A, Tangianu F, Tocco F, Concu A, Mameli O, Mulliri G, Caria MA. Ischemic preconditioning of the muscle improves maximal exercise performance but not maximal oxygen uptake in humans. J Appl Physiol 2011; 111: 530–536 7 de Groot PC, Thijssen DH, Sanchez M, Ellenkamp R, Hopman MT. Ischemic preconditioning improves maximal performance in humans. Eur J Appl Physiol 2010; 108: 141–146 8 Deschodt VJ, Arsac LM, Rouard AH. Relative contribution of arms and legs in humans to propulsion in 25-m sprint front-crawl swimming. Eur J Appl Physiol 1999; 80: 192–199 9 Figueiredo P, Sanders R, Gorski T, Vilas-Boas JP, Fernandes RJ. Kinematic and electromyographic changes during 200 m front crawl at race pace. Int J Sports Med 2013; 34: 49–55 10 Gibson N, Mahony B, Tracey C, Fawkner S, Murray A. Effect of ischemic preconditioning on repeated sprint ability in team sport athletes. J Sports Sci 2014; doi:10.1080/02640414.2014.988741 11 Gibson N, White J, Neish M, Murray A. Effect of ischemic preconditioning on land based sprinting in team sport athletes. Int J Sports Physiol Perform 2013; 8: 671–676 12 Harriss DJ, Atkinson G. Ethical standards in sport and exercise science research: 2014 update. Int J Sports Med 2013; 34: 1025–1028 13 Hollander AP, De Groot G, van Ingen Schenau GJ, Toussaint HM, De Best H, Peeters W, Meulemans A, Schreurs AW. Measurement of active drag during crawl arm stroke swimming. J Sports Sci 1986; 4: 21–30 14 Ikuta Y, Matsuda Y, Yamada Y, Kida N, Oda S, Moritani T. Relationship between decreased swimming velocity and muscle activity during 200-m front crawl. Eur J Appl Physiol 2012; 112: 3417–3429



Training & Testing

15 Jean-St-Michel E, Manlhiot C, Li J, Tropak M, Michelsen MM, Schmidt MR, McCrindle BW, Wells GD, Redington AN. Remote preconditioning improves maximal performance in highly trained athletes. Med Sci Sports Exerc 2011; 43: 1280–1286 16 Lalonde F, Curnier DY. Can anaerobic performance be improved by remote ischemic preconditioning? J Strength Cond Res 2015; 29: 80–85 17 Libonati JR, Cox M, Incanno N, Melville SK, Musante FC, Glassberg HL, Guazzi M. Brief periods of occlusion and reperfusion increase skeletal muscle force output in humans. Cardiologia 1998; 43: 1355–1360 18 Morouco P, Keskinen KL, Vilas-Boas JP, Fernandes RJ. Relationship between tethered forces and the four swimming techniques performance. J Appl Biomech 2011; 27: 161–169 19 Murry CE, Jennings RB, Reimer KA. Preconditioning with ischemia: a delay of lethal cell injury in ischemic myocardium. Circulation 1986; 74: 1124–1136


IJSM/4763/17.4.2015/MPS

20 Paixao RC, da Mota GR, Marocolo M. Acute effect of ischemic preconditioning is detrimental to anaerobic performance in cyclists. Int J Sports Med 2014; 35: 912–915 21 Patterson SD, Bezodis NE, Glaister M, Pattison JR. The effect of ischemic preconditioning on repeated sprint cycling performance. Med Sci Sports Exerc 2014; doi:10.1249/MSS.000000000000576 22 Stirn I, Jarm T, Kapus V, Strojnik V. Evaluation of muscle fatigue during 100-m front crawl. Eur J Appl Physiol 2011; 111: 101–113 23 Tocco F, Marongiu E, Ghiani G, Sanna I, Palazzolo G, Olla S, Pusceddu M, Sanna P, Corona F, Concu A, Crisafulli A. Muscle ischemic preconditioning does not improve performance during self-paced exercise. Int J Sports Med 2015; 36: 9–15


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