In the last 20 yr, rock climbing has risen in popularity worldwide and has become a competitive international sport (20,28). Among international elite climbers, "lead" competition is one of the more prized forms of practice. In this competition, the best climbers are usually not limited by the time allocated (often 12 min) to finish the route, by technical difficulties, or by quality of the preview but by exhaustion. This state of exhaustion is characterized by pain in forearms and impossibility to maintain a required hand position on grips preventing the climber to complete the climbing route (21). The routes used in "lead" competitions are mostly on the basis of vertical displacements on an overhanging wall which seems more physiologically demanding compared with other types of routes as reflected by HR, lactate concentration, and RPE (8). Blood lactate concentrations can remain elevated for up to 30 min after a climb (34).
"Lead" climbing competitions often require the ascent of multiple climbing routes (three to five routes), including qualifications, semifinal, final, and sometimes superfinal, during the course of several hours. Quite often, the routes are separated by only a short period of recovery, e.g., 20 min. Thus, the quality and capacity of recovery seems one of the determinant factors for optimal competition climbing performance.
To date, however, only two studies have investigated recovery in rock climbers (10,36). They compared the effects of passive and active recovery on lactate, RPE, and HR. Although it was shown that blood lactate decrease was hastened by active recovery within the 2 to 20 min after intense climbing, no study tried to establish whether this effect can be advantageous to subsequent climbing performance (36). And yet, even when active recovery (15 min) improves lactate removal after an intense anaerobic exercise, it does not necessarily improve performance in a subsequent anaerobic exercise of the upper body (14).
Several other modalities of recovery have been used in many sports, but never in climbing. Electromyostimulation involves the transmission of electrical impulses via surface electrodes to peripherally stimulate motor neurons eliciting muscular contractions. It has been suggested that these contractions may be advantageous to recovery because of increased blood flow via the "muscle pump effect," which may enhance tissue repair (3).
When performed after intense eccentric exercises, cold water immersion (CWI) may reduce exercise-induced muscle damage and perceived soreness (2,12,33). Precooling results in a better exercise endurance, with enhanced heat storage rate and less stress on metabolic and cardiovascular systems (16).
In addition to the effectiveness of CWI as a postexercise recovery as well as a precooling strategy, Vaile et al. (32) very recently reported positive effect of 15-min intermittent CWI recovery in 10 to 15°C water in maintaining subsequent high-intensity cycling performance in the heat. To our knowledge, the effects of such an intervention on repeated intense exercises in thermoneutral conditions have never been examined. Because Pohl et al. (23) showed that 5-min CWI of the hands and forearms at 15°C performed between two writing performances in patients with writer's cramp was able to improve a subsequent writing performance, this might also be the case in climbing. The authors hypothesized that this positive effect of CWI might result from a reduction in muscle spindle activity by lowering muscle temperature.
With these considerations in mind, the aim of this randomly assigned crossover study was to examine the effects of four recovery modalities on blood lactate, HR, skin temperatures, RPE, handgrip strength, and subsequent maximal climbing performance. It was hypothesized that active recovery, electromyostimulation, and CWI would allow a better recovery than passive modality and hence would be beneficial for the subsequent exhausting climbing performance.
The study protocol was approved by the ethical committee of the Vrije Universiteit Brussel. Subjects were recruited from local competitive rock climbing clubs and were required to have a minimum of 3-yr climbing experience. After verbal and written explanation of the testing procedures, 13 trained female climbers (age 27.1 ± 8.9 yr) accepted to participate and completed the written informed consent and a health history questionnaire.
Preliminary Laboratory Examination
Before participation, all subjects underwent a medical and physical examination. Body composition (TBF-300 Body Composition Analyzer; Tanita Corp., Tokyo, Japan), regular physical activity (questionnaire), and climbing history (years climbing, years competing, climbing ability, and amount of training) were assessed. Before leaving the laboratory, the subjects underwent a 5-min familiarization with immersion of arms and forearms in cold water (15°C).
All the subjects were tested at the same period of the year (April and May). Subjects came to the climbing center on four occasions separated by 1 wk. On each occasion, the subjects completed the same standardized warm-up consisting of three warm-up routes (rating according to French grading system for technical difficulty: 5b, 5c, 6a) with 10-min rest in between. Twenty minutes after the last warm-up route, the subjects had to perform two climbing tests (C1and C2) until volitional exhaustion. These two tests were separated by 20 min of recovery (Fig. 1). Four recovery methods were used in randomized order: passive recovery, active recovery, electromyostimulation, and CWI. The effects of recovery methods on performance and physiological parameters at C2 compared with C1 and on physiological parameters during the 20-min recovery were assessed. Subjects were requested to refrain from vigorous exercise and climbing for 48 h and from eating at least 2h before each testing occasion. The subjects were also asked to keep a constant training program throughout the 4 wk of study. The temperature in the climbing center remained constant between 20°C and 24°C during the experiments.
The two climbing tests (C1 and C2) consisted of repeating a specific "top-roping" route until volitional exhaustion. The same route was used for C1 and C2 and at every climbing test occasion. This route was overhanging (inclined 35° to the vertical) and was 22 m in length. Difficulty of the route was subjectively rated at 6b on the French grading system for technical difficulty by consensus of the staff of route-setters used by the climbing center. The route had from the start to the end the same difficulty, meaning that easy resting spots or boulder passages were minimized. Before their first testing day, the subjects were asked to "work out the moves" of the testing route. The speed at which subjects had to climb was not dictated because we wished to simulate a field setting performance. However, the subjects were encouraged to climb continuously and pauses on holds for rest or putting chalk on hands were not permitted to last longer than 4 s. At the completion of the route, tension was applied to the safety rope, and the subjects were quickly lowered to the ground. Immediately after touching the ground, they had to restart climbing the same route. This exercise approach was repeated until exhaustion defined as the fall.
Performance at C1 and C2 was reflected by the total duration of climbing and the number of arm movements performed. The duration of climbing was measured with a stopwatch and defined as the time between the first hold taken and the fall minus the time spent for each lowering down.
Between C1 and C2, the subjects recovered for 20 min. Four types of recovery (passive, active, electromyostimulation, and CWI) were used in randomized order. Passive recovery involved resting in a seated position on a bench with the arms along the body. During the active recovery, the subjects had to pedal on a cycle ergometer at a constant workload of 30-40 W. This intensity of lower limb exercise has been reported to likely increase brachial arterial blood flow (15). The pedaling rate was set between 50 and 70 rpm (5), corresponding to the commonly freely chosen pedaling rate in noncyclists. Electromyostimulation (Endomed 982; Enraf Nonius, Delft, the Netherlands) was performed on the right and left forearm flexor muscles while the subjects were seated on a bench. A bisymmetric TENS current, starting at a frequency of 9 Hz, was used. This frequency was decreased by 1 Hz every 2 min until reaching 7 Hz. From then on, the frequency was reduced by 1 Hz every 3 min until reaching 2 Hz (31). The subjects selected the most comfortable intensity (i.e., levels between 15 and 20 μA). This type of current was chosen as a method for passive muscle contraction and is currently used in commercial electromyostimulation devices designed for athletes. Moreover, using this protocol of electromyostimulation, Tessitore et al. (31) observed positive effects on perceived muscle pain 5h after the exercise and the 20-min recovery period. CWI was performed by submerging arms and forearms in two tubs of water set beside the subject seating on a bench (12). The hands leaned on the rim of the tubs, outside the water. The arms and forearms protocol of immersion involved three periods of 5 min in the water, separated by 2 min dried outside the water. Considering previous reports (19,38), the water was maintained at a temperature of 15 ± 1°C (by adding ice cubes, cold or hot water, previously practiced ina pilot study). Each recovery period was followed by 1.5min of passive recovery seated on a bench to enable subjects to refocus for the subsequent climbing test (10).
Arterialized blood samples (20 μL) were taken at the earlobe before warming up, before and after C1 and C2, and after 10 min of recovery (Fig. 1). Samples were stored in a cooling box pending analysis, the same day, for blood lactate concentration (Biosen 5030; EKF, Magdeburg, Germany). Before and after C1 and C2, as well as at several times during recovery (Fig. 1), seated HR (Accurex Plus; Polar®, Kempele, Finland), RPE (4), thermal sensation (21-point scale ranging from unbearable cold to unbearable heat; adapted from Parsons ), and right and left handgrip strength (single-measurement efforts with an handgrip dynamometer (Model 78010; Lafayette Instrument Company, Lafayette, IN) were assessed. The order of measurements was kept constant before and after C1 and C2, starting with HR, then RPE and ratings of thermal sensation, followed by handgrip strength and lastly by blood lactate sampling.
At several times during the 20-min recovery period (Fig. 1), weighted mean skin temperatures (24) were assessed with surface skin temperature probes (Gram Corporation LT-8 A, Saitama, Japan), the measuring side being carefully placed in direct contact with skin on the hand flexor on the forearm, on the brachial biceps (both submerged in case of CWI recovery), on the shoulder, and on the chest (both out the water in case of CWI recovery). The temperature probes were insulated against environment influence with waterproof adhesive tape.
Statistics were computed using Statistica 6.0 software (StatSoft, Tulsa, OK). Results are reported as means ± SD except where otherwise indicated. Normality was tested using Kolmogorov-Smirnov tests. All measurements taken before warm-up as well as before and after C1 were compared between the four recovery testing occasions by one-way repeated-measures ANOVA (parametric data) or Friedman ANOVA (nonparametric data) to check for the absence of initial differences. The effect of the recovery methods on climbing performance, on postclimbing levels of lactate, HR and handgrip strength, and on lactate and HR increase during climbing test was assessed with two-way ANOVA (recovery method × climbing test number) with repeated measures on both factors. The effect of the recovery methods on change in HR, lactate, and temperatures throughout the 20 min of recovery was analyzed using two-way ANOVA (recovery method × recovery time) with repeated measures on both factors. If significant main effects were observed with ANOVA, Duncan's multirange post hoc tests were applied to examine specific pairwise differences. Nonparametric data (i.e., RPE, thermal sensation) were analyzed using Friedman ANOVA and Wilcoxon's matched pairs tests. P<0.05 was considered statistically significant.
All subjects had experience in sport climbing competitions. Their self-reported experience with rock climbing was 7.7 ± 8.0 yr. Their climbing ability, defined as self-reported best sport-style route climbed "on lead after work," ranged from 6b to 7b+ (French grading system for technical difficulty) on indoor overhanging wall. Descriptive characteristics of the subjects are presented in Table 1.
Measurements before the Recovery Interventions
Before warm-up as well as before and after C1, HR, blood lactate, handgrip strength, RPE and thermal sensation scale were comparable for the four recovery testing occasions (Figs. 2 and 3). Duration of climbing and number of arm movements at C1 did not significantly differ among the four recovery testing occasions (Table 2).
Effect of the Recovery Method on Climbing Performance
No adverse effects (pain or unpleasant sensation) were reported by the subjects during the four recovery procedures. A significant interaction between climbing test number and recovery method was evident for performance, as assessed by duration of climbing and number of movements (P < 0.05). Performance was impaired at C2 compared with C1 when electromyostimulation or passive recovery was used (P < 0.005), whereas C1 performance was maintained at C2 after active recovery and CWI recovery (Table 2).
Effect of the Recovery Method on Physiological Parameters
Right and left handgrip strengths were lower post-C1 and -C2 compared with pre-C1 and -C2 (P < 0.001; Fig. 2). These strength levels were lower at pre-C2 than at pre-C1, whereas levels at post-C2 did not differ from levels at post-C1. There was no significant difference between right and left strength and between recovery modalities.
There was no significant effect of the recovery method on RPE levels during recovery or subsequent climbing test. RPE increased significantly during climbing tests (e.g., from 11.0 ± 2.5 to 15.6 ± 2.4 at C1 and from 12.5 ± 2.1 to 16.1 ± 1.8 at C2 for passive recovery testing trial; P<0.01). RPE decreased significantly throughout the 20-min recovery period for all the recoveries (P < 0.01) but remained higher at pre-C2 than at pre-C1 (P < 0.05). RPE at climbing exhaustion was comparable for C1 and C2.
HR increased significantly during climbing tests (P< 0.001) without any differences between C1 and C2 and among the four recovery testing occasions (Fig. 3A). Throughout the 20-min recovery period, HR was significantly higher for active recovery compared with the three other recoveries (P < 0.001). However, the refocusing phase after active recovery allowed the HR to return to levels comparable to those of other recovery methods. Pre-C2 HR was comparable to pre-C1 HR for all the recovery methods.
Blood lactate levels.
Blood lactate decreased during the four recovery interventions (P < 0.001) with differences in their decrease slopes (time-by-recovery method interaction, P < 0.001; Fig. 3B). The greatest decrease occurred for active recovery with lactate levels achieving the lowest levels (at 10 and 20 min of recovery; P < 0.05), whereas passive recovery was associated with the highest lactate levels (at 10 and 20 min of recovery) compared with other methods (P < 0.05). At the end of the 20-min recovery (pre-C2), blood lactate levels were higher than levels before C1 (pre-C1) for electromyostimulation, CWI, and passive recovery (P < 0.001), whereas they returned to pre-C1 levels after active recovery. Blood lactate increased less during C2 than during C1 for the four testing occasions (Table 3). Between-recovery differences in the increase slopes were observed at C2 (interaction pre-/post-C2 levels-by-recovery method, P < 0.005) with a greater slope for active recovery compared with passive and CWI recoveries (P < 0.005). Post-C2 blood lactate levels were comparable to post-C1 levels and did not differ among the four recovery testing occasions.
Skin temperature and rating of thermal sensation.
Throughout the 20-min recovery, skin temperatures of biceps and forearm were significantly lower during CWI compared with other recovery modalities (P < 0.001; Fig. 3C). Temperatures of shoulder and chest, which were always out the water, did not differ among the recovery modalities and were stable throughout recovery at around 33°C.
Throughout the 20-min recovery period, ratings of thermal sensation were significantly higher during active recovery and significantly lower during CWI recovery compared with the other recovery methods, indicating that subjects felt warmer and colder, respectively (P < 0.05; Fig. 3D). Thermal sensation at post-C2 was comparable to post-C1 levels and did not differ among the recovery methods.
The present randomly assigned crossover study aimed at comparing the effects of four recovery methods (active, passive, electromyostimulation, and CWI) on lactate concentration, skin temperatures, RPE, HR, and the subsequent maximal climbing performance in indoor climbing. The main finding was that CWI and active recovery were more effective in maintaining subsequent climbing performance than electromyostimulation and passive recovery.
The subjects included in the present study represent a well-conditioned and expert-level group of female sport competitive climbers. Their anthropometric characteristics are comparable to those of female climbers of similar climbing levels tested in other studies (20,35).
The climbing exhaustive test used in the current study was well representative of a competition route type terrain. The duration of the climb, approximately 6 to 9 min, corresponds to exhaustion time usually observed in "lead" competitions. Blood lactate at climbing exhaustion was comparable to that obtained from the earlobes of 46 competitors after route ascents during World Championship competition (37).
The recovery modalities were designed to be easily usable in the climbing environment especially in isolation areas to which climbers are confined before on-sight competitive routes.
Although CWI and active recovery had positive effects on subsequent performance in our study, in accordance with Watts et al. (36), the recovery method had no effect on the change in handgrip strength during the 20-min recovery period. However, it should be reminded that the grip position used during standard handgrip dynamometer testing does not often occur during climbing. Therefore, handgrip dynamometer testing may probably not be specific enough to detect a level of fatigue that would affect climbing performance (36).
In accordance with Watts et al. (36) and with researches in other sports (1), only active recovery allowed blood lactate to return to baseline levels after the 20-min recovery. This is probably due to cardiovascular adaptations, including an increase in HR as observed in the current study, allowing an increase in blood flow and thus a faster redistribution of lactate to alternative metabolism sites such as the liver, the heart, and muscles (39). Increased energy demand at a low intensity to support the active recovery (cycling exercise) could also be a factor of faster removal of lactate because lactate may serve as a substrate. Blood lactate levels after active recovery were lower by approximately 0.37 to 1.24 mmol·L−1 than lactate levels at the end of other recovery modalities. Hence, in line with the results of Draper et al. (10), the range of increase in lactate during the climbing test was greater after active recovery compared with other recovery modalities. This finding could partly explain the positive effect of active recovery on subsequent performance because lactate production may help to retard acidosis and facilitate proton removal from muscle (26), hence delaying fatigue (25). However, it remains that blood lactate represents, at best, an indirect indicator of lactate production and oxidation from the whole body.
The major finding of our study is that the 20-min intermittent CWI allowed the subsequent climbing performance to be preserved. Very recently, Vaile et al. (32) showed that whole-body CWI was effective in maintaining a high-intensity cycling performance in the heat. Our study suggests that local CWI may also be effective for repeating intense exercises in thermoneutral conditions.
In our study, the depth of water being less than 70 cm, water hydrostatic pressure is probably not responsible for the beneficial effects of CWI on subsequent performance (38).
CWI was not associated with an increase in HR in our study. This result is not surprising considering that only the arms were immersed. In another study involving whole-body head-out immersion in water at 14°C, body temperature decreased by approximately 1.7°C, which probably induced a stimulation of thermogenesis and activation of the sympathetic nervous system, as evidenced by the increases in noradrenaline concentrations, HR, and blood pressures, which were greater than in thermoneutral water (30).
The skin temperatures recorded during CWI in the present study were comparable to those of immersed body parts measured by Castle et al. (6) with similar probes in water at 17.8 ± 2.1°C during 20 min. In our study and that of Castle et al. (6), an interaction between cold water environment and temperature probes might probably not be fully avoided despite the precautions taken. However, besides skin temperatures, Castle et al. (6) also measured the corresponding muscle temperatures using intramuscular probes. From their results, we can hypothesize that there was a real decrease in forearm and arm muscle temperatures of approximately 1.5°C with CWI in our study. This represents a local muscle cooling.
Several mechanisms might explain the positive effects of local muscle cooling during recovery on subsequent performance. Climbing involves endurance against an eccentric force for upward propulsion (35). After a damage-inducing eccentric exercise of the elbow flexors, Eston and Peters (12) reported beneficial effects of 15-min CWI of the arms on muscle stiffness and the amount of postexercise damage. Local cooling indeed decreases the rate of transmission along neurons, which contributes to the relief of pain (analgesia) and alleviates muscle spasm (19). Although the presence of edema after climbing remains to be checked in future research, it is well known from empirical observations that exhaustion in climbing coincides with increase in forearm circumferences and pain in forearms (21). Therefore, in our study, localized vasoconstriction induced by local cooling may have reduced acute inflammation from muscle damage via a reduction of vessel permeability (12,33). This in turn can have reduced pain and the loss of force generation (29,38). Thus, in the present study, a presumable delayed sensation of pain or discomfort and reduction in muscle spasticity associated with local cooling might have contributed to postpone exhaustion at the subsequent climb.
Although 20-min electromyostimulation recovery has been shown to be also effective in decreasing muscle pain, this positive effect was observed 5 h after the exercise and recovery period (31). It might so be possible that positive effects of electromyostimulation would appear when interval between exercises would be longer than 30 min.
Besides the reduction in pain, the alleviating effect of local cooling on inflammation and edema might also have beneficial effects on metabolism during recovery. Edema in response to strenuous exercise or muscle damage may increase both the transport route and compression of local capillaries, reducing oxygen delivery to localized cells (38). Thus, it could be hypothesized in our study that the potential effect of cold water immersion on edema may have improved oxygen delivery to arm and forearm muscles. This seems very important because we know that muscle reoxygenation during recovery phases may be a predictor of endurance performance in climbing (18). Moreover, based on the study of Yanagisawa et al. (40), CWI may have accelerated normalization of intracellular pH.
Metabolism during subsequent exercise may also be affected by precooling. An elevation of muscle temperature is known to speed the rate of glycogenolysis and phosphate production by as much as 10% (17), causing quicker fatigue (11) and reduced mean power output (17). Therefore, starting the subsequent climb with lower muscle temperatures might have delay metabolic acidosis caused by an increased reliance on nonmitochondrial ATP turnover (26), thus delaying exhaustion.
Lastly, it should be noted that the intermittent protocol used in our study for CWI and the last short period of resting in ambient air were set to allow subjects to recover from peripheral vasoconstriction and presumably increase preliminary perfusion of arm muscles.
Although CWI had a clear positive effect on subsequent performance in our study, caution should be taken when using it. Some people can present hypersensitivity to cold and be at risk if body parts are suddenly immersed in cold water (38). Besides the need for individualization, the protocol of cold immersion should be very specific. For example, an immersion in water at lower temperatures (10°C for 5 to 20 min) would probably decrease isometric grip strength (9). Besides, a longer and greater depth immersion in cold water (1 h up to the abdomen) could impair muscle blood flow and oxygen supply, hence increase lactate accumulation during the rest-to-work transient (13).
It should also be reminded that our findings about CWI between climbing performances typical of "lead" competitions are probably not directly generalized to apply to other types of climbing competitions such as "bouldering" or "speed climbing." Although reduction in pain may be of benefit, a reduced neural transmission may decrease muscular contractile speed and force-generating ability of an athlete after application (7,27).
This study demonstrated the relevance of a 20-min recovery with CWI and moderate cycling but not electromyostimulation or passive rest on subsequent exhaustive climbing performance. CWI is a simple, cheap, and safe procedure, providing new perspectives in terms of recovery guidelines during competitions. This study has also repercussions in terms of training because climbers will generally not wait up to 30 min before completing a further exercise trial. Cycling and CWI might thus improve the climber's capability to regain an adequate working state for subsequent exercises during a training session.
Future investigations should examine the combination of active recovery and CWI recovery modalities because the mechanisms involved in enhanced performance might be specific and independent.
Disclosure of funding for this work: we received no funding for this work.
The authors thank P. Pico and J.-F. Cloots from Stone Age climbing center (Woluwe, Brussel) for the use of their climbing facility and P. Lievens, A. Tassenoy, J. Heyman, and F.-X. Gamelin for their advice and technical assistance. The results of the present study do not constitute endorsement by ACSM.
1. Ahmaidi S, Granier P, Taoutaou Z, Mercier J, Dubouchaud H, Prefaut C. Effects of active recovery
on plasma lactate and anaerobic power following repeated intensive exercise. Med Sci Sports Exerc
2. Bailey DM, Erith SJ, Griffin PJ, et al. Influence of cold-water immersion on indices of muscle damage following prolonged intermittent shuttle running. J Sports Sci
3. Barnett A. Using recovery modalities between training sessions in elite athletes: does it help? Sports Med
4. Borg G, Dahlstrom H. The reliability and validity of a physical work test. Acta Physiol Scand
5. Carnevale TJ, Gaesser GA. Effects of pedaling speed on the power-duration relationship for high-intensity exercise. Med Sci Sports Exerc
6. Castle PC, Macdonald AL, Philp A, Webborn A, Watt PW, Maxwell NS. Precooling leg muscle improves intermittent sprint exercise performance in hot, humid conditions. J Appl Physiol
7. Crowe MJ, O'Connor D, Rudd D. Cold water recovery reduces anaerobic performance. Int J Sports Med
8. de Geus B, Villanueva O'Driscoll S, Meeusen R. Influence of climbing style on physiological responses during indoor rock climbing on routes with the same difficulty. Eur J Appl Physiol
9. Douris P, McKenna R, Madigan K, Cesarski B, Costiera R, Lu M. Recovery of maximal isometric grip strength following cold immersion. J Strength Cond Res
10. Draper N, Bird EL, Coleman I, Hodgson C. Effects of active recovery
on lactate concentration, heart rate and RPE in climbing. J Sports Sci Med
11. Drust B, Rasmussen P, Mohr M, Nielsen B, Nybo L. Elevations in core and muscle temperature impairs repeated sprint performance. Acta Physiol Scand
12. Eston R, Peters D. Effects of cold water immersion
on the symptoms of exercise-induced muscle damage. J Sports Sci
13. Ferretti G, Binzoni T, Hulo N, Kayser B, Thomet JM, Cerretelli P. Kinetics of oxygen consumption during maximal exercise at different muscle temperatures. Respir Physiol
14. Franchini E, Yuri Takito M, Yuzo Nakamura F, Ayumi Matsushigue K, Peduti Dal'Molin Kiss MA. Effects of recovery type after a judo combat on blood lactate removal and on performance in an intermittent anaerobic task. J Sports Med Phys Fitness
15. Green D, Cheetham C, Reed C, Dembo L, O'Driscoll G. Assessment of brachial artery blood flow across the cardiac cycle: retrograde flows during cycle ergometry. J Appl Physiol
16. Lee DT, Haymes EM. Exercise duration and thermoregulatory responses after whole body precooling. J Appl Physiol
17. Linnane DM, Bracken RM, Brooks S, Cox VM, Ball D. Effects of hyperthermia on the metabolic responses to repeated high-intensity exercise. Eur J Appl Physiol
18. MacLeod D, Sutherland DL, Buntin L, et al. Physiological determinants of climbing-specific finger endurance and sport rock climbing performance. J Sports Sci
19. Meeusen R, Lievens P. The use of cryotherapy in sports injuries. Sports Med
20. Mermier CM, Robergs RA, McMinn SM, Heyward VH. Energy expenditure and physiological responses during indoor rock climbing. Br J Sports Med
21. Morrison AB, Schöffl VR. Physiological responses to rock climbing in young climbers. Br J Sports Med
22. Parsons K. Human Thermal Environments
. London (UK): Taylor & Francis; 2003. p. 53-4.
23. Pohl C, Happe J, Klockgether T. Cooling improves the writing performance of patients with writer's cramp. Mov Disord
24. Ramanathan NL. A new weighting system for mean surface temperature of the human body. J Appl Physiol
25. Raymer GH, Marsh GD, Kowalchuk JM, Thompson RT. Metabolic effects of induced alkalosis during progressive forearm exercise to fatigue. J Appl Physiol
26. Robergs RA, Ghiasvand F, Parker D. Biochemistry of exercise-induced metabolic acidosis. Am J Physiol Regul Integr Comp Physiol
27. Rutkove SB. Effects of temperature on neuromuscular electrophysiology. Muscle Nerve
28. Sheel AW. Physiology of sport rock climbing. Br J Sports Med
29. Smith LL. Acute inflammation: the underlying mechanism in delayed onset muscle soreness? Med Sci Sports Exerc
30. Srámek P, Simecková M, Janský L, Savlíková J, Vybíral S. Human physiological responses to immersion into water of different temperatures. Eur J Appl Physiol
31. Tessitore A, Meeusen R, Cortis C, Capranica L. Effects of different recovery interventions on anaerobic performances following preseason soccer training. J Strength Cond Res
32. Vaile J, Halson S, Gill N, Dawson B. Effect of cold water immersion
on repeat cycling performance and thermoregulation in the heat. J Sports Sci
33. Vaile J, Halson S, Gill N, Dawson B. Effect of hydrotherapy on the signs and symptoms of delayed onset muscle soreness. Eur J Appl Physiol
34. Watts P, Newbury V, Sulentic J. Acute changes in handgrip strength, endurance, and blood lactate with sustained sport rock climbing. J Sports Med Phys Fitness
35. Watts PB. Physiology of difficult rock climbing. Eur J Appl Physiol
36. Watts PB, Daggett M, Gallagher P, Wilkins B. Metabolic response during sport rock climbing and the effects of active versus passive recovery. Int J Sports Med
37. Werner I, Gerbert W. Blood lactate responses to competitive climbing
. In: Messenger N, Patterson W, Brook D, editors. The Science of Climbing and Mountaineering, Chapter 3 (CD-ROM)
. Champaign (IL): Human Kinetics Software; 2000.
38. Wilcock IM, Cronin JB, Hing WA. Physiological response to water immersion: a method for sport recovery? Sports Med
39. Wilmore JH, Costill DL. Physiology of Sport and Exercise
. 2nded. Champaign (IL): Human Kinetics; 1999. p. 116-7. (ISBN 0-7360-0084-4).
40. Yanagisawa O, Niitsu M, Takahashi H, Goto K, Itai Y. Evaluations of cooling exercised muscle with MR imaging and 31
P MR spectroscopy. Med Sci Sports Exerc