9 Powerful Reasons to Warm-Up for Rock Climbers – Quick summary
- Warm-up for rock climbers – Introduction
- A good warm-up helps prevent injury and enhances performance
- Critical training tool
- Warm up for rock climbers – Physiological effects
- Temperature related effects of a warm-up for rock climbers
- Effects of an active warm-up for rock climbers
- The role of stretching in a training session
- Helps increase the range of motion (ROM)
- Decreases muscle soreness
- Eases muscle spasms
- Stretching does not necessarily reduce injury risk
- Stretching before a training session significantly reduces strength and power!!
- Stretching after a training session promotes faster recovery
- Warm-up for rock climbers – Summary and conclusions
- Enhances performance and helps prevent injuries
- Helps increase ROM and boosts anaerobic and aerobic metabolism
- Allows to maintain optimum muscle temperature through a cold climbing day
- Must be time-efficient and contribute to the athlete’s short term and long term development
- Climbers should pay special attention to warming-up fingers and shoulders
Warm-up for rock climbers – Introduction
The majority of climbers and athletes know the importance of a solid warm-up before hitting the rock or the gym wall. Coaches, physiotherapists, and doctors generally recommend doing warm-up, stretching, and cool-down exercises to prevent injury and enhance performance . Numerous studies have shown that a proper warm-up is indeed an effective way of reducing injury risk .
But there is far more than meets the eye when it comes to getting yourself ready for a hard climbing training session. For the climbing warm-up routine to let us maximize the performance on the rock or at the climbing gym, it needs to be well structured, specific, and time-efficient. Ideally, the transition between the warm-up and the main session should be seamless. Preparatory exercises need to be designed to contribute directly to the main session’s activities and goals. But most importantly, you should treat the warm-up in itself as a critical training tool rather than solely a preparation before the actual training . So, let’s go ahead and take a closer look at the essential aspects of an effective warm-up for rock climbers.
Warm-up for rock climbers – Physiological effects
Warm up techniques are divided into two primary categories: passive and active. The goal of a passive warm up is to raise the muscle temperature (Tm) or core temperature (Tc) by external means, such as hot showers or baths, saunas, diathermy, and heating. Such an approach makes it possible to warm the body without depleting energy substrates, which are needed later during the main activity .
An active warm-up for rock climbers may involve jogging, jumping, push-ups, pull-ups, fist-clenching, and some light climbing, leading to more significant metabolic and cardiovascular changes than the passive warm-up. The warm-up’s primary effects can be divided into temperature related and non-temperature related, as shown in Table 1 
Table 1: Physiological effects of a warm-up.
|Decreased resistance of muscles and joints|
|Increased muscle and ligament flexibility|
|Enhanced blood flow to muscles|
|Speeding of metabolic reactions|
|Increased speed of nerve impulses (conduction rate)|
|Enhanced blood flow to muscles|
|Elevation of baseline oxygen consumption|
Temperature related effects of a warm-up for rock climbers
When talking about body temperature, we need to distinguish between the core temperature (Tc) and the temperature of the muscles and ligaments (Tm). The core itself is generally defined as the brain and the heart, and its temperature is kept stable at 37°C .
The muscles and ligaments in the arms and legs serve as radiators that remove excess heat from the core, and their temperature usually is 2 – 6°C below the core temperature . Generally, the further the muscle and ligament tissues are from the central body, the cooler they are, so forearm muscles and fingers get cold very easily .
In Figure 1 below, the forearm muscle temperature measured at different depths from the skin’s surface is plotted . Before taking the measurements, the forearm was immersed in a water bath of different temperatures for 30 minutes, and one reference measurement was done at room temperature in air. Water is a much better heat conductor than air, so the temperature at 2 cm below the skin at 26°C, measured for the forearm immersed in water is about 5°C lower than the temperature measured if the forearm is air-cooled. That means that if we are climbing outside, wearing only a t-shirt, taking long rests between burns, and it is below 20°C outside, the forearm muscles’ temperature may drop below 30°C, compromising performance.
The easiest way to warm-up deep tissues such as muscles is by light active exercise, which increases the blood flow and moves the heat from the core to the further parts of the body . But since blood flow in ligament tissues is much lower than in the muscles, it is better to heat knees, ankles, and finger joints externally . Warming your cold fingers by rubbing them together can indeed help reduce injury risk, but it may also be a good idea to take a heat pack to the crag during the chilly fall and winter months.
Reason 1: Heat improves tendon flexibility – decreased resistance of muscles and jointsThe impact of heat on the flexibility of knee ligaments was investigated by Petrofsky and his team in 2013 . They applied cold packs and heat packs to the knee joints of male and female subjects and measured the knee ligament laxness and the force needed to flex the knee. Then they compared the results with data collected at room temperature. The results of their findings are plotted in Figure 2 and Figure 3.
Figure 2: The displacement per newton force for the anterior (AC) and posterior (PC) cruciate ligaments in 10 subjects ± the Standard Deviation. Data was collected at room temperature and 20 minutes after cold pack application or 20 minutes after application of hydrocollator heat packs or 4 hours after application of heat wraps .
Figure 3: Newtons of force per degree movement of the quadriceps per kg body weight to move the knee into flexion. Mean for 10 subjects ± the Standard Deviation .
It is clear that after applying cold packs to the knee joint for 20 minutes, the displacement of the cruciate ligaments per newton of force decreased and the force required to flex the knee joint increased. In contrast, after applying heat for 20 minutes using hydrocollator heat packs and after applying heat for 4 hours through heat wraps, the knee ligaments became more flexible, and 25% less force was required to bend the knee compared to the situation when cold was applied.
Reason 2: Increased blood flow to musclesIn 1942 it was already shown by Barcroft and Edholm that external temperature (water immersion) significantly influences blood flow in the forearm Figure 4 . Adequate blood flow plays a vital role in oxygen and substrate delivery to the muscles and removes the accumulated metabolites. Thus it is crucial to ensure that the arms and back are warm throughout the climbing day.
Figure 4: Average forearm blood flow at different water-bath temperatures, five subjects. The arm was placed in the water at time 0 .
Reason 3: Increased anaerobic metabolism
Although increased muscle temperature (Tm) does not impact resting muscle metabolism, it does enhance muscle glycogenolysis and glycolysis. It also accelerates the high-energy phosphate (ATP and phosphocreatine) production and breakdown during exercise . Such an increase in anaerobic metabolism benefits both short-term and intermediate performance.
The effect is illustrated in Figure 5 , where it is shown that ATP production quickly slows down if the muscle temperature drops below the resting 35°C. These results indicate that keeping your muscles warm is likely to improve performance on pumpy endurance routes and speed up recovery between bouldering attempts.
Figure 5: Anaerobic adenosine triphosphate (ATP) supply during exercise at different muscle temperatures (Tm). Rates are expressed as a percentage of normal (100%) .
Reason 4: Greater maximum force and duration of sustained contractionsIn 1958 Clarke et al. investigated the duration and the maximum force of sustained contractions exerted by the human forearm at different temperatures . They measured the flexor muscles’ contraction duration at about 33% of the maximum force produced at room temperature. The Figure 6 shows that the longest contraction durations were recorded after a 30-minute immersion in a water bath of 18°C. That corresponds to a muscle temperature of about 27°C at 2 cm under the skin surface.
Figure 6: Mean durations of sustained forearm contractions at about 33% MVC in water at seven temperatures .
Figure 7: The individual and average maximal tensions, expressed as a percentage of initial maximum tension, recorded after the forearm had been immersed in water at each of the seven temperatures for 30 min. .
Reason 5: Higher rate of force development (RFD)Muscle temperature has a significant impact on the contraction velocity. If your muscles get cold, it will have a detrimental effect on your performance, particularly during fast movements . In cold muscles, the chemical reactions responsible for contractions become slower , the cross-bridge cycle is delayed , and the sensitivity of actomyosin to calcium is reduced . What is more, low temperature increases antagonist muscle activity, which serves as a protective mechanism for muscles and joints . A warm-up helps counteract these effects and enhances the performance in cold environments .
Effects of an active warm-up for rock climbers
An active warm-up’s direct effects are more difficult to assess because any exercise inevitably leads to a concurrent temperature increase of the muscles  (Figure 8). That causes the thermal and non-thermal effects to combine, and their impact may be hard to evaluate separately. But an active warm-up indeed introduces additional protective effects since it increases the range of motion and helps stretch the muscle-tendon junction, which is the most common site of failure .
Figure 8: Temperature measured at rest, during moderate exercise and during recovery for the rectal (Tr), skin (Ts) and muscle at a probe deph of approximately 20 mm (Tm20) and 40 mm (Tm40), in commonly observed ambient conditions (10 – 30°C) .
Reason 6: Pre-conditioning contractions reduce injury riskIn 1988 Safran et al. investigated the impact of pre-conditioning contractions on the incidence of muscle tears. The team focused on the force and change of length required to tear the muscle, site of failure, and length-tension deformation. They found that muscles that were isometrically loaded before the task could stretch further, became more elastic, and handled more force before failure than the non-preconditioned ones Figure 9 .
Figure 9: Average force to failure for preconditioned and unconditioned TA, EDL, and FDL muscles. All values are means ± SD, N = 60 .
Figure 11: Force of physiological bowstringing acting on the distal edge of the A2 pulley; External force in N against flexion applied at the pulp od the distal phalanx horizontally; Force component if flexor tendons in N, which causes bowstringing vertically .
Reason 7: Aerobic metabolism kicks in earlierAnother interesting effect of an active warm-up is that it improves oxygen metabolism. While it appears that warming-up does not increase the oxygen consumption kinetics, it does allow subsequent tasks to begin at an elevated baseline oxygen consumption. That means that less of the initial work is done anaerobically, which spares more anaerobic capacity for later, effectively increasing the time to exhaustion and improving performance (see Figure 12) . That effect can be incredibly helpful on routes where the crux is located high up after a long section of relatively easy climbing.
Figure 12: Schematic representation of the aerobic and anaerobic contribution to an all-out task without (a) and with (b) prior warm up. O2Eq = oxygen equivalents; V̇O2 = oxygen consumption .
Reason 8: Postactivation Potentiation (flexor muscle recruitment)
If you are interested in climbing training, you probably heard the term “muscle recruitment,” and you know that it is essential to complete some high-intensity hangs before starting the climbing session. These near-maximum pre-conditioning hangs allow improved performance on the rock, precisely why many climbers carry portable hangboards to the crags. Once I even read someone say that climbing without prior recruitment is like forgetting to put on your climbing shoes.
The correct name for the effect of enhanced performance after the prior high-intensity effort is Postactivation Potentiation (PAP). According to the definition, Postactivation potentiation is the temporary increase in muscle contractile performance following previous ‘conditioning’ contractile activity . This phenomenon has been thoroughly researched and well documented, as the power output of both the upper and lower extremities was reported to increase after PAP interventions .
The performance enhancement caused by PAP is typically explained by enhanced neural activation. That includes an increase in motor unit stimulation/recruitment, improved motor unit synchronization, and/or decreased presynaptic inhibition. The combination of these processes results in greater cross-bridge attachments within the muscle, effectively allowing the muscle to generate more force .
The critical thing to remember in order to maximize the potentiation benefits is to rest for about 3 – 5 minutes before beginning the climb. Otherwise, residual fatigue from the pre-conditioning hangs may interfere with the climber’s performance. Still, waiting too long will diminish the twitch potentiation, so the optimum rest duration is a trade-off between activation and recovery, as shown in Figure 13 .
Reason 9: Reduced Delayed Onset of Muscle Soreness (DOMS)
Pretty much everyone has experienced muscle soreness after training. This dull pain is common at the start of a strength training program or when athletes perform unfamiliar exercises that engage previously untrained muscle groups. Muscle soreness is particularly frequent during the first few days of eccentric training when the athletes use loads that are heavier than what they are used to. That comes as no surprise because higher tension leads to more muscle damage .
One of the most noticeable damage types is the disruption of the muscle cell membrane , leading to elevated creatine kinase levels – a marker of muscle damage – lasting for up to 48 hours after the training session. Since the discomfort is usually felt during the first 24 to 48 hours following the training session, the effect is called delayed onset muscle soreness (DOMS) .
Interestingly, warming-up also reduces the severity of DOMS 48 hours after exercise that involved a high eccentric component . The muscle soreness comes from myofibrils that were damaged by stretching . As the muscle temperature rises during the warm-up by roughly 3 deg C, the structures around the myofibrils become more elastic and compliant . This helps reduce the extent to which the myofibrils are stretched, resulting in less myofibrillar damage and, consequently, lesser DOMS .
The role of stretching in a training session
I think that when discussing warm-up, it is necessary to address the topic of stretching at least briefly. It is not uncommon for climbers to perform stretching routines as part of their warm-up activities. Indeed, stretching helps increase the range of motion (ROM), decrease muscle soreness, and ease muscle spasms .
It is also commonly believed that stretching helps prevent injuries, although this is not necessarily true. In his review, Shrier concluded that stretching prior to exercise is unlikely to reduce injury risk . Moreover, recent studies have shown that stretching before a training session can be counterproductive, as it can result in a 5 – 30% reduction in both strength and power for up to one hour . For these reasons, static stretching should not be performed for the muscles that are going to be trained in a strength or power session unless it is placed at the beginning of a long warm-up routine .
Warm-up for rock climbers – Summary and conclusionsThere are essentially two types of warm-up, passive and active. Both lead to body temperature elevation, which has positive effects on performance and reduces susceptibility to injuries. However, an active warm-up has some additional advantages. It helps increase the range of motion or leads to higher initial V̇O2. On the other hand, a passive warm-up may be useful in maintaining high body temperature throughout the climbing day, especially if the weather is cold. The most important physiological effects of a warm-up are:
- Improved tendon elasticity,
- Enhanced blood flow to the muscles
- Elevated anaerobic and aerobic metabolism
- Higher muscle contractile force and rate of force development
- Better nerve conduction rate
- Postactivation potentiation (aka “recruitment”)
While a general warm-up is essential for all athletes, rock climbers should pay specific attention to shoulders and fingers. The small rotator cuff muscles and finger pulleys are repetitively subjected to excessively high loads, making them particularly prone to all kinds of traumatic and overuse injuries. Therefore, rock climbers must warm up the shoulders and fingers dynamically to increase their range of motion and ensure sufficient connective tissue elasticity. Nevertheless, while static stretching helps aid recovery, you should reserve it for after the training session. Intense stretching done before climbing has a significant negative effect on strength and power.
To sum up, a proper warm-up is a critical training tool in any sport. For the warmup to be effective, the following considerations must be taken into account :
- Does it contribute to both long term and short term development?
- Is it well structured?
- Is it time-efficient?
- Does it contribute to other session aims?
Applying these principles directly into a well-structured warm-up for climbers is a topic for a more extended discussion, and I will address it in other posts.
If you have any questions or comments, feel free to contact me. Please subscribe to the blog, to keep up to date with the upcoming posts on cutting edge methods of climbing training!
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