Strength and Conditioning for Dancers

Our bodies are reactive mechanisms in that they adapt in response to a stimulus being added or taken away.34 If a stimulus is new or greater than previously experienced then there is an anabolic (training) adaptation; if a stimulus is removed then there is a catabolic (detraining) adaptation. Interestingly, if a stimulus stays the same, the body learns to carry out the activity more efficiently and there is a slight detraining effect. Finding the appropriate stimulus can initially be a case of trial and error and involves your training age and physical competency.

TRAINING AGE

This refers to the number of years' experience you have in a particular activity. There can be some transference in training years between activities, but it depends on the similarities between the activities: the skills developed, primary muscles used, type of contraction, activity length, and force generated. Therefore, you could have a ballet training age of fifteen years, jazz training of five years, Pilates of five years and no years of strength training. One of the limitations of early specialization is that training years have been built up in one activity often to the exclusion of others, which can cause anatomical imbalances and also limit training age transference between different activities.

PHYSICAL COMPETENCE

This refers to an individual's ability to develop new movement skills and patterns. This is obviously highly developed within dancers and you, the dancer, can pick up new movements very quickly. The downside to this is that often the underlying anatomical development cannot develop at the same rate and this can leave you vulnerable to injury. Therefore, often a prolonged period of foundational training is required for the body's structures to develop sufficiently to keep up with your movement abilities.

TRAINING STIMULUS

The stimulus we place on the body needs to be specific to the goals we want to achieve, and these will be discussed in more detail in Chapter 4. For improvements to occur we need to stress a system beyond what it is used to. If too much stress is applied, then the system will break; if not enough, no improvements occur, or detraining can start to happen. This load can be monitored in a number of different ways depending on the activities being undertaken.

Time under tension

This denotes the amount of time a muscle is under tension during a strength or power training session. It mainly refers to the work:rest ratio of a session - in other words, the number of repetitions of an exercise, the number of sets of repetitions, how long the muscle is under tension during the set, and the rest between the sets (for example, 4 sets of 10 repetitions with 2 minutes' rest between the sets). This, in combination with the force being exerted, will determine how a muscle adapts to the training stimulus. Increased time under tension (little rest between training sets) with high levels of force (training load) will have a hypertrophic effect (increases in muscle mass) as it has been shown to increase the release of testosterone, growth hormone and cortisol; a lower time (more rest between training sets) under tension with a similar training load will have a neuromuscular effect (increased co-ordination, fibre recruitment). The chosen training load also determines the time under tension: if a very heavy training load is chosen, the more rest is needed between sets to recover and therefore the adaptations become more neuromuscular; moderate to heavy training loads require less recovery, thereby increasing the time under tension and promoting hypertrophy; very light loads with lots of repetitions have long time periods under tension but because of the light load don't cause hypertrophy (the muscle may change shape but the volume rarely changes). Therefore, the amount of rest you have during a training session has a fundamental effect on how your muscle responds to training.

Weight moved

This refers to the total weight moved/lifted in a training session. For instance, a leg training session might encompass:

Squats: 2 × 10 reps at 50kg; 2 × 6 reps at 100kg

Straight leg deadlifts: 2 × 10 reps at 80kg; 2 × 6 reps at 100kg

Calf raises: 4 × 15 reps at 80kg

Therefore, the total weight moved for this session is 9,800kg

Training impulse (TRIMPS)

This is mainly used for cardiorespiratory training sessions. You record the length of the training session in minutes and multiply this by either the mean heart rate or rate of perceived exertion. Heart rate should be recorded/monitored via a chest band monitor to a watch, rather than solely via a watch, as the latter is less accurate. The Rate of Perceived Exertion, the sRPE ('s' refers to session), monitors how hard you felt the session was. This was developed by Borg,35 who noted that perceived exertion was related to heart rate and developed a scale ranging from 6-20 (if you add a 0 to the numbers you get the equivalent heart rate to the perceived exertion); this has been further adapted to include a 1-10 scale as well. You can use either scale, though you need to be consistent in which one you choose. The top scores refer to maximal effort, whilst the bottom ones relate to resting states (Fig. 4).

Fig. 4 Rate of perceived exertion scales.

Therefore a 20-minute session on a cross-trainer could be classified in the following ways:

Table 3 Recording sRPE.

Foot contacts

Quite simply this is the number of repetitions of high impact exercises that encompass hops, jumps and bounds. This monitoring system is usually solely used for plyometric training but can also be incorporated into dance training monitoring to record the number of jumps and hops in classes and rehearsals. This is particularly important after a holiday period when a gradual increase in contact loading has been shown to reduce the incidence of lower leg injuries such as shin splints.

Dance training

Your dance activities need to be taken into account as well, a number of studies have shown that sRPE is a valid measure of intensity across a number of dance genres.36 Using the same model as TRIMPS, you multiply the sRPE by the length of the dance session (minutes) to calculate the session load.

MONITORING TRAINING LOAD

Generally, the body can cope with a 5-10 per cent increase in overall load a week; this is the accumulated load of all your activities - dance, supplemental training, rehabilitation, leisure activities - using the above training stimuli monitoring tools. Because you are training multiple components all at once it is imperative that it is the overall training load that increases each week, and not each component you are training. As dance is your primary activity (the other training components are there to support your dance), this training load takes precedence. Therefore, if your rehearsal and/or performance schedule starts to increase drastically then you might need to decrease the training load from supplemental training so that the overall load remains within the 5-10 per cent band increase.

Each of the supplemental training components will have an individual importance for yourself depending on your current physical status and the demands of your dance schedule (see Needs Analysis in Chapter 4). As you can't train every component at the same time (see Scheduling Training section of this chapter) each component will have a descending level of importance, with some components being in 'maintenance mode' (trained just once a week to maintain previous improvements), whilst others are the main focus. When it comes to increasing your overall training load, it is the latter group that receives the increased training stimulus.

ADAPTATION AND SUPERCOMPENSATION

During exercise, muscles go through a catabolic period with the breakdown of molecules to release energy (ATP to ADP+Pi) and the breakdown/damage of muscle proteins. In the recovery or anabolic phase, the muscle cells work to replenish energy stores and repair the damaged protein structures (Fig. 5). If the training stimulus is more than previously experienced the muscle cells prepare to be able to cope with the new stimulus by either storing more energy or building more protein structures (hypertrophy), but if the training stimulus remains constant there is little or no adaptation (Fig. 5).

Fig. 5 The catabolic and anabolic effect of a single training session.

RECOVERY

Recovery is fundamental to optimal training, although it has taken a while to be recognized as an integral training component. Research has shown that depending on the type of training stimulus, the recovery time can vary quite markedly; this is measured in the time it takes for protein synthesis to return to normal levels post-exercise. As you can see from Fig. 6, intense anaerobic and strength training can take between 40 and 72 hours after the training session to recover; this doesn't mean you can't use those muscles in the interim period, but they won't be able to work optimally, and you are more likely to prolong the recovery period.

Fig. 6 Recovery periods for different...