While working on Mobility for Swimmers, I realized the benefits of dynamic stretching/warm-up, especially when compared to static stretching. I wrote an extensive series on Swimming World about static stretching [Part I, Part II, Part III] and the main conclusion was static stretching may impair performance and strength gains, but more importantly is likely a waste of time! The defending champion Cal Bears implement a dynamic warm-up before they enter the water and anecdotally they’re reaping the benefits (as you’ll see). Dynamic stretching/warm-up is a different form of stretching which can enhance performance and decreases the need for a long-labored swimming warm-up.
What is Dynamic Mobility?
Dynamic stretching is moving the body freely through its available range of motion. Now, this definition may seem simple, but the applications for swimming may be dramatic! For this reason, many top teams are having their swimmers perform these unorthodox warm-ups before a meet and practice. As you’ll see, the benefits of dynamic stretching are worth the extra ~10 minutes!
Research Review on Dynamic Stretching
Dynamic Stretching and Acute Power
Power is the amount of energy consumed per unit time. Skilled swimmers generate high
amounts of power during the start, turn and catch phase of most strokes. Research suggests dynamic stretching before an activity increases acute power. The mechanism behind this improvement is not well unknown, but may simply be by warming-up the body. Luckily, dynamic stretching appears to improve the power of the knee extensors (Manoel 2008). In fact, it seems power is greater following dynamic stretching compared to other forms of stretching.
Dynamic Stretching on Acute Performance
Power is great, but no gold medals are awarded for power production. Instead, performance is the main guide in swimming. Unfortunately, many studies only analyze power.
Remember, performance parameters are key. Unfortunately, many studies only analyze
power or force, yet these do not always translate to performance. When reading the research, keep this in mind!
In another study, the effects of different stretching were also assessed on vertical jump height. This study found collegiate athletes had the greatest vertical jump after dynamic stretching or dynamic flexibility(Holt 2008).
General warm-up and general warm-up + dynamic warm-up resulted in greater countermovement jump height (Pagaduan 2013).
Dynamic stretching had greater vertical jump performance enhancement in recreationally trained athletes (Perrier 2011).
Dynamic warm-up significantly increased relative strength index and flight time compared to static and only warm-up groups (Werstein 2012).
A few studies have found decreases in torque after dynamic stretching. However, these studies still showed improvements in performance (Pagaduan 2012; Holt 2008; Perrier 2011).
Dynamic stretching doesn’t improve or impair endurance performance during a 30-minute time trial (Zourdos 2012).
It also seems dynamic stretching is most beneficial 3 – 5 minutes before the performance (Turki 2011).
Summary:
Dynamic stretching has been shown to improve performance (measured by the vertical jump). When combined with a general aerobic warm-up, dynamic stretching also appears to further enhance performance. Dynamic stretching also doesn’t need to be before an activity, as it has been shown to improve performance 3 – 5 minutes before an activity.
Practical Implication for Swimmers
Perform a 10 – 15-minute dynamic warm-up ~3 – 5 minutes before warming up. This practice can warm-up the body and increase power and performance gains.
Theoretical Reasons for Dynamic Stretching
Improved power and performance are two of the researched reasons for using dynamic stretching. Here are two other theoretical reasons for using dynamic stretching/warm-up
- Less in Water Warm-up Required: A dynamic warm-up increases the body temperature. This warm-up decreases the time needed for a slow, poorly performed in-water warm-ups.
- Improved Motor Control [body coordination]: Many swimming warm-ups use the same motions as swimming [ie freestyle is used as the main warm-up and during the main set]. This lack of variety does not enhance general motor control. In fact, slow and sloppy in-water warm-up may impair stroke biomechanics and motor control. Unlike swimming warm-ups, out of water dynamic warm-up can enhance an athlete’s motor control.
- General Strength Gains: Many people have sedentary lives. This lack of movement variety creates muscular imbalances which may increase injury risk. Mastering varying movements with a dynamic warm-up can enhance general strength, which may help a swimmer control their body, but more importantly, help create a balanced muscular system and prevent injuries.
4 Things for the Perfect Dynamic Warm-up
- Include the Entire Body: Using the entire body entourages improved motor control and full body connection. Also, using the whole body increases the body temperature faster than isolated warm-ups. Now, every movement doesn’t require a full body motion, but starting from one joint and progressing to multiple joints can teach functional integration and warm-up the body.
- Use all the Planes of Motion: In our basics section, we break down the various planes of motion. Using each plane of motion of the main joints (humerus, femur, etc.) uses various muscle groups to activate and increase the body temperature.
- Mix-up the Exercises: Once again, this is a great opportunity for motor control enhancement, as well as general strength gains. In the States, many children do not perform physical education class, resulting in excessive sitting and screen time. A dynamic exercise with frequently changing exercises can enhance motor control, with the goal of helping children control their body and increase the capacity for movement adjustment and biomechanical improvement in the pool.
- Warm them up!: The entire routine doesn’t require a high-intensity movement [nor should it fatigue the swimmer], but it must increase the body temperature. This allows the swimmer to hit the water ready to perform beneficial work, not just sloppy swimming.
Example Dynamic Warm-up
Now, many routines are possible, but here is one dynamic warm-up [for an athlete with poor shoulder internal rotation] which encompasses the four points above:
Self Myofascial Releases (SMR):
- SMR Infraspinatus
- Rotary SMR Thoracic spine
Dynamic Warm-up:
3 Rounds
- 20 Glenohumeral Joint Internal Rotation
- 50 High Knees
- 20 Bulgarian Dead Lift
- :60 Side-Steps with Robots
- 20 Push-up Back Touches
- 20 Lunge with Rotation
References:
- Pagaduan JC, Pojskić H, Užičanin E, Babajić F. Effect of various warm-up protocols on jump performance in college football players. J Hum Kinet. 2012 Dec;35:127-32. doi: 10.2478/v10078-012-0086-5. Epub 2012 Dec 30.
- McMillian DJ, Moore JG, Hatler BS, Taylor DC. Dynamic vs. static stretching warm up: the effect on power and agility performance. J Strength Cond Res. 2006; 20:492-499.
- Costa PB, Herda TJ, Herda AA, Cramer JT.Effects of Dynamic Stretching on Strength, Muscle Imbalance, and Muscle Activation.Med Sci Sports Exerc. 2013 Sep 24. [Epub ahead of print].
- Manoel ME, Harris-Love MO, Danoff JV, Miller TA. Acute effects of static, dynamic, and proprioceptive neuromuscular facilitation stretching on muscle power in women. J Strength Cond Res. 2008 Sep;22(5):1528-34. doi: 10.1519/JSC.0b013e31817b0433.
- Werstein KM, Lund RJ.J The effects of two stretching protocols on the reactive strength index in female soccer rugby players Strength Cond Res. 2012 Jun;26(6):1564-7.
- Perrier ET, Pavol MJ, Hoffman MA. The Acute Effects of a Warm-up including static or dynamic stretching on countermovement jump height, reaction time, and flexibility. J Strength Cond Res. 2011 Jul; 25(7):1925-31.
- Turki O, Chaouachi A, Drinkwater EJ, Chtara M, Chamari K, Amri M, Behm DG. Ten minutes of dynamic stretching is sufficient to potentiate vertical jump performance characteristics.J Strength Cond Res. 2011 Sep;25(9):2453-63. doi: 10.1519/JSC.0b013e31822a5a79.
Comments 1
Very interested in your work.