4 Things for the Perfect Dynamic Swimming Warm-up

Take Home Points on 4 Things for the Perfect Dynamic Swimming Warm-up

  1. Dynamic warm-up improves power production and performance.
  2. Dynamic warm-ups may also decrease in-water warm-up time and improve motor control.
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 IPart 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 it's 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 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 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 performance (Turki 2011).

Summary:
Dynamic stretching has been shown to improve performance (measured by 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
  1. 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. 
  2. 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. 
  3. 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

  1. 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. 
  2. 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. 
  3. 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. 
  4. Warm them up!: The entire routine doesn't require a high-intensity movements [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):

  1. SMR Infraspinatus
  2. Rotary SMR Thoracic spine 

Dynamic Warm-up:

3 Rounds
  1. 20 Glenohumeral Joint Internal Rotation
  2. 50 High Knees
  3. 20 Bulgarian Dead Lift
  4. :60 Side-Steps with Robots [First year of the KADP...got to love the oversized shirts!]
  5. 20 Push-up Back Touches
  6. 20 Lunge with Rotation

References:

  1. 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.
  2. 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. 
  3. 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]. 
  4. 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. 
  5. 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. 
  6. 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. 
  7. 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.
Written by G. John Mullen received his Doctorate in Physical at University of Southern California (USC) and is a certified strength and conditioning specialist (CSCS). At USC, he was a clinical research assistant performing research on adolescent  diabetes, lung adaptations to swimming, and swimming biomechanics. G. John has been featured in Swimming World Magazine, Swimmer Magazine, and the International Society of Swim Coaches Journal. He is currently the owner of COR, providing Physical Therapy, Personal Training, and Swim Lessons to swimmers and athletes of all skills and ages. He is also the creator of the Swimmer's Shoulder SystemSwimming ScienceSwimming Science Research Review, and the Swimming Troubleshooting System.

Warm-up and Swimming Performance

Take Home Points on Warm-up and Swimming Performance 

  1. If performing a warm-up, in-water warm-up appears most effective.
Warm-up is commonly performed by every swimmer. The role of swarm-up in sprint swimming was discussed recently in best Warm-up for Sprint Swimming Performance. It is believed a warm-up increases muscle temperature, stimulate the performance of muscle contraction, decrease the time to achieve peak tension and relaxation, and reduce the viscous resistance of the muscles and joints. Warm-up also leads to increased blood flow, up-regulating blood vessel dilation and increasing muscle oxygenation. Warm-up may also decrease lactate accumulation after a 30 s sprint (Gray 2002). However, lactate accumulation does not always correlate with performance, an important distinction. 

Looks like a good warm-up to me!
Despite evidence suggesting warm-up improves performance, warm-up has also been shown to impair performance (Stewart 1998; Di Cagno 2010). 

Now, the literature on swimming warm-up and performance is scarce, making it important to keep the research in mind, then make the best plan possible. The research is rarely crystal clear and swimming warm-up demonstrates this again. Luckily this review article by Nieva et al. helps provide some answers on the subject. 

The Study: Warm-Up and Performance in Competitive Swimming. Neiva HP, Marques MC, Barbosa TM, Izquierdo M, Marinho DA.  Sports Med. 2013 Nov 1. [Epub ahead of print]

Active Warm-up and Swimming Performance

Active warm-up typically involves specific or non-specific body movements with the purpoose of increasing heat. This is the most common form of warm-up. Active warm-ups demonstrated swimming improvements in 67% of the studies comparing an active swimming warm-up to no warm-up. 

The effects of active warm-up depend on several components (intensity, volume, recovery, etc.) which make it difficult to control. 

Dry-land Warm-up and Swimming Performance

Dry-land warm-up involves performing calisthenics, strength, or stretching outside of the water before performance. Some feel a dry-land warm-up does not improve performance compared to no warm-up (Romney 1993), but one study demonstrated a 1.23% improvement with a dry-land warm-up (Romney 1993).

Despite theoretical possibility, the use of resistance training before exercise to stimulate motor neurons, has not been shown in swimming. Two studies looking at resistance training before swimming demonstrated no differences in swimming or starting performance (Kilduff 2011).

Many competitions have a period between in water warm-up and swimming performance. Swimmers typically fill this void with dry-land warm-up, yet no studies have looked at this appropriateness.

Stretching is another modality commonly used before swimming. Unfortunately, other athletic studies have demonstrated static stretching (for less than 30 seconds) likely impairs performance see Friday Interview: Dr. David Behm Discusses Stretching). However, specific studies on swimming have yet to be performed.

How Much Swimming Warm-up Improves Performance?

Swimming volume is one manipulated variable for swimming warm-up. Two studies found positive effects for volumes between 1,000 and 1,500 m (Houmard 1991; Balilionis 2012). Other studies have found no difference between warm-up volumes (Arnett 2002). 

Some studies have found impaired performance after sprint swimming warm-up (Neiva 2012). This may be due to depleting the body energy during warm-up. 

Overall, Neiva (2013) suggests a 15 - 20 minute warm-up (between 1,000 - 1,500 m) for events up to 3 - 4 minutes. Warm-up in the morning may need longer duration to increase body temperature.

What Swimming Intensity Maximizes Performance?

Few studies have analyzed different swimming warm-up intensities. Houmard found no difference between warming up a 65% or 95% VO2max (Houmard 1991). However, other studies have found warming-up at 110% of VO2max increases lactate concentrations after a 200-yard race (Mitchell 1993). 

Pretty intense warm-up...right?
Warm-up should be intense to increase body temperature, but not overly fatigue the swimmer. The rest between warm-up and the race must also be considered. 

How Much to Recover After Warm-up?

Two studies have compared different lengths between warm-up and competition. The 200 -m times were 1.38 and 1.48% improved between with a 10-min or 20-min rest period, compared to a 45 min rest (West 2013; Zochowski 2007). This may be from the post-activation potentation of warm-up. 

Studies have only analyzed the 200-m freestyle, but it seems a rest period of 8 - 20 minutes is ideal between warm-up and competition.

Does Passive Warm-up Help Swimming Performance?

Body temperature is manipulated by many mechanisms, including heat packs, saunas, and showers. It is believed increasing muscle temperature by 1 degrees Celsius improves performance by 2 - 5% (Racinais 2010). 

Carlilie (1956) found a positive effect of a hot shower or a 10-minute massage, where De Vries did not find any improvement with a 10-m massage (1959) (see Does Massage Improve Soreness?)

More randomized studies are clearly needed on this subject, as many swimmers perform these practices. 

Warm-up for Different Races

Different races clearly require different warm-ups, as different distances have different intensities and metabolic demands. It seems warm-up is beneficial for races 200-m and longer, and likely beneficial for 100-m races. More studies are necessary on the 50-m race. It is also important to consider the day-to-day or test-to-test variations (Neiva 2013). 

Conclusion

If performing a warm-up, in-water warm-up appears most effective. When water is not available, dry-land exercises can be used as an alternative (Functional Swimming Warm-up). More studies are necessary for determining if the 50-m does require a warm-up, or if day-to-day variability has resulted in some of the negative warm-up effects.

Related Reading

References

  1. Neiva HP, Marques MC, Barbosa TM, Izquierdo M, Marinho DA. Warm-Up and Performance in Competitive Swimming. Sports Med. 2013 Nov 1. [Epub ahead of print]
  2. Gray SC, Devito G, Nimmo MA. Effect of active warm-up on metabolism prior to and during intense dynamic exercise. Med Sci Sports Exerc. 2002 Dec;34(12):2091-6.
  3. Stewart IB, Sleivert GG. The effect of warm-up intensity on range of motion and anaerobic performance. J Orthop Sports Phys Ther. 1998 Feb;27(2):154-61.
  4. Di Cagno A, Baldari C, Battaglia C, Gallotta MC, Videira M, Piazza M, Guidetti L. Preexercise static stretching effect on leaping performance in elite rhythmic gymnasts. J Strength Cond Res. 2010 Aug;24(8):1995-2000. doi: 10.1519/JSC.0b013e3181e34811.
  5. Romney RC, Nethery VM. The effects of swimming and dryland warm-ups on 100-yard freestyle performance in collegiate swimmers. Journal of Swimming Research,1993; 9, 5-9.
  6. Kilduff LP, Cunningham DJ, Owen NJ, West DJ, Bracken RM, Cook CJ. Effect of postactivation potentiation on swimming starts in international sprint swimmers.
  7. J Strength Cond Res. 2011 Sep;25(9):2418-23. doi: 10.1519/JSC.0b013e318201bf7a.
  8. Houmard JA, Johns RA, Smith LL, Wells JM, Kobe RW, McGoogan SA. The effect of warm-up on responses to intense exercise. Int J Sports Med. 1991 Oct;12(5):480-3.
  9. Balilionis G, Nepocatych S, Ellis CM, Richardson MT, Neggers YH, Bishop PA. Effects of different types of warm-up on swimming performance, reaction time, and dive distance. J Strength Cond Res. 2012 Dec;26(12):3297-303. doi: 10.1519/JSC.0b013e318248ad40.
  10. Arnett MG. Effects of prolonged and reduced warm-ups on diurnal variation in body temperature and swim performance. J Strength Cond Res. 2002 May;16(2):256-61.
  11. Neiva HP, Marques MC, Fernandes RJ, Viana JL, Barbosa TM, Marinho DA. Does Warm-Up Have a Beneficial Effect on 100m Freestyle? Int J Sports Physiol Perform. 2013 Apr 9. [Epub ahead of print]
  12. Neiva Hp, Morouco PG, Pereira FM. The effect of warm-up in 50 m swimming performance. Motricidade. 2012; 8 (S1): 13-18.
  13. Mitchell JB, Huston JS.The effect of high- and low-intensity warm-up on the physiological responses to a standardized swim and tethered swimming performance.J Sports Sci. 1993 Apr;11(2):159-65.
  14. Houmard JA, Johns RA, Smith LL, Wells JM, Kobe RW, McGoogan SA. The effect of warm-up on responses to intense exercise. Int J Sports Med. 1991 Oct;12(5):480-3.
  15. West DJ, Dietzig BM, Bracken RM, Cunningham DJ, Crewther BT, Cook CJ, Kilduff LP. Influence of post-warm-up recovery time on swim performance in international swimmers. J Sci Med Sport. 2013 Mar;16(2):172-6. doi: 10.1016/j.jsams.2012.06.002. Epub 2012 Jul 11.
  16. Zochowski T, Johnson E, Sleivert GG. Effects of varying post-warm-up recovery time on 200-m time-trial swim performance. Int J Sports Physiol Perform. 2007 Jun;2(2):201-11.
  17. Racinais S, Oksa J. Temperature and neuromuscular function. Scand J Med Sci Sports. 2010 Oct;20 Suppl 3:1-18. doi: 10.1111/j.1600-0838.2010.01204.x. Review.
  18. Calile F. Effect of preliminary passive warming on swimming performance. Res Q Exerc Sport, 1956; 27(2):143-51. 
  19. De Vries HA. Effects of various warm-up procedures on 100-yard times of competitive swimmers. Res Q. 1959; 30: 11-22.
G. John Mullen received his Doctorate in Physical at University of Southern California (USC) and is a certified strength and conditioning specialist (CSCS). At USC, he was a clinical research assistant performing research on adolescent diabetes, lung adaptations to swimming, and swimming biomechanics. G. John has been featured in Swimming World Magazine, Swimmer Magazine, and the International Society of Swim Coaches Journal. He is currently the owner of COR, providing Physical Therapy, Personal Training, and Swim Lessons to swimmers and athletes of all skills and ages. He is also the creator of the Swimmer's Shoulder System, Swimming Science, Swimming Science Research Review, and the Swimming Troubleshooting System.

Warm-up and Swimming Performance

Take Home Points on Warm-up and Swimming Performance

  1. Warm-up is individualized for the person, as well as the event and goal.
  2. Dynamic warm-ups are likely more appropriate than static stretching.

Research suggests warm-up to improve athlete’s performance by significant margins. However, it is something that is rarely discussed and often overlooked by many coaches. Planning the components stimulated in a session depends on the requirements of the individual athlete, the microcycle, and the macrocycle where the session occurs. Warm-ups should include event specific movements to stimulate the proper neuromuscular action for the range of motion and correct posture. Warm-ups for training and competition needs to consider the demands of each individual athlete.

Warm-up and Body Temperature

Every session of training or competition should begin with a general warm-up. These activities should to involve all body components and aim to increase the temperature of the large and deep muscles. Swimming is a unique activity because each athlete enters a pool of water typically held between 78-80 degrees. Simply entering a swimming pool decreases the body temperature of that athlete by about 3 degrees. This makes long warm-ups consisting of slow swimming erroneous because it is almost impossible to increase body temperature while partaking in low heart-rate activities in a water-cooled environment.

Warm-up and Flexibility

Flexibility should always follow activities that make muscles warm because warm muscles
and joint structures are more flexible than cold ones and are less prone to injury. Dr. Brent Rushall bluntly states that “the common practice of stretching on deck then swimming a ‘warm-up’ is wrong” (Rushall, 1999). A study done in 2008 looking at collegiate track and field athletes found that “static muscle stretching can negatively impact the performance of a skill that demands repetitive high power outputs even when preceded by a dynamic warm-up protocol (Winchester et al., 2008).” Dynamic stretching as a part of warm-up has been found to yield positive results for land activities. Also pointed out by Rushall is the fact that, “Rarely, if ever, will there be an experienced swimmer, who has participated in high school and club swimming and entered the college ranks, with a performance-limiting restricted range of movement in the important swimming joints” (Rushall, 2009). So perhaps just a short, stroke-specific swim is all that is necessary for experienced swimmers when warming up for swimming workouts. If flexibility is a weakness, dynamic stretching is likely to yield much greater results than static stretching. Please see Josh Pintar’s article “Practical Static and Dynamic Stretching for Swimmers” for a much more detailed look at this topic specifically

Timing of Warm-up

Swimmers have been found to compete faster when racing 20 minutes post-warm-up when compared to 45 minutes (West et al., 2012). These findings suggest that warming up closer to one’s race will lead to more desirable results. Coaches can assume the same for race pace training. Dr. Brent Rushall recommends a brief warm-up (a maximum of five minutes) before partaking in a USRPT set. “Swimmers should be warm from land warm-up work, and the pool work is basically a brief familiarity experience. Getting straight into repetition work is more like the competitive experience where swimmers spend more than 20 minutes not in the pool before racing” (Rushall, 2013).

Specificity of Warm-up

Research has shown that effort levels similar to those required in a following task precipitated better endurance performances (Burnley, 2005). This supports the notion that warm-ups should match intended performance intensity. This would nullify reasoning to go through a sprint warm-up when preparing for an endurance set or competition as well as the opposition wherein an endurance warm-up is given before a sprint set.

Individuality of Warm-up

Swimmers within a group exposed to the same training program respond with varied and different physiological adaptations (Howat and Robson, 1992). This points to the role the principle of individuality plays in all aspects of training, warm-up is no different. Simply generalizing a singular warm-up to all athletes of a heterogeneous group may not bring desired results.

Practical Implications

Structuring warm-up according to current scientific literature will begin with a general activity that warms the muscular, skeletal system followed by flexibility, and concluded with event specific exercises. The effect swimming pools have on body temperature needs be considered during general warm-up. Limiting static stretching or replacing it with active movements would be better suited to stimulate flexibility if needed before a set/competition. Warming up closer to the competition (~20 minutes) has been found to lead to greater success in swim performance. Specific intensities as well as individual’s needs should also be taken into consideration when designing a warm-up.

Related Warm-up Articles

References:

  1. Rushall, Brent. (1999) “The structure of training sessions according to scientific principles.” Swimming Science Bulletin. Web. 15 Nov. 2013.  
  2. Winchester JB, Nelson AG, Landin D, Young MA, Schexnayder IC. Static stretching impairs sprint performance in collegiate track and field athletes. J Strength Cond Res. 22 Jan 2008(1):13-9. 
  3. Rushall, Brent. “The Future of Swimming: Myths and Sciences.” Swimming Science Bulletin (2009): Swimming Science Bulliten. Web. 15 Nov. 2013.  
  4. West, D. J., Dietzig, B. M., Bracken, R. M., Cunningham, D. J., Crewther, B. T., Cook, C. J., & Kilduff, L. P. (2012). Influence of post-warm-up recovery time on swim performance in international swimmers. Journal of Science and Medicine in Sport, 15, 6 pages (http://www.sciencedirect.com/science/article/pii/ S144024401200120X).
  5. Rushall, Brent. “Step-By-Step USRPT Planning and Decision Making.” Swimming Science Bulletin (2013): Swimming Science Bulletin. Web. 15 Nov. 2013.  
  6. Howat, R. C., & Robson, M. W. (June, 1992). Heartache or heartbreak. The Swimming Times, 35-37.Burnley, M., Doust, J. H., & Jones, A. M. (2005). Effects of prior warm-up regime on severe intensity cycling performance. Medicine and Science in Sports and Exercise, 37(5), Supplement abstract 437.

Herbert Behm is a long time swimmer and coach, currently Assistant Coaching the Senior and Age Group programs at Phoenix Swim Club in Phoenix, Arizona. He is completing his Bachelor of Arts degree in Psychology and Communications at Arizona State University where he is a school record holder in the 400 Medley Relay.

Best Warm-up for Sprint Swimming Performance


Take Home Points on the Best Warm-up for Sprint Swimming Performance

  1. Regular warm-up is the best warm-up for sprint swimming performance, for most.
  2. No warm-up or a short warm-up may best the best warm-up for some swimmers.
  3. Individual warm-up protocols are necessary for sprint swimming performance.

Warm-up (WU) is performed by nearly all swimmers with the goal of increasing heart rate (HR), blood flow, body temperature, and preparing the body for competition/practice. However, many swimmers use an extremely long WU compared to their race distance, potentially causing fatigue. A highly pertinent study looked at what was the best warm-up for sprint swimming performance.

What was done

Sixteen NCAA Division 1 swimmers (M=8, F=8; ~19.9 years; mean male time ~21.96 s, mean female time ~24.35 s) used three WUs before performing a 50-yard freestyle time trial. The three warm-ups were

  1. No WU
  2. Short WU (50-yard at 40% of max and 50-yard at 90% max)
  3. Regular WU (~1300 m)

Results

The mean 50-yard time was significantly faster after the regular WU when compared to the short WU. However, individual data indicated 19% of the participants performed their best 50-yard after a short WU, 37% after no WU, and 44% after regular WU.


HR was significantly higher after regular WU, compared to no WU. No differences were noted in reaction time, rating of perceived exertion post 50-yard, dive distance, or stroke count across the different trials.

Discussion

Regular WU increases HR more than no WU and causes significantly better times than a short WU. However, the principle of individuality is key, as some athletes performed best times with short or no WU [very surprising, as these were not the swimmers typical WU approach and novelty typically hinders performance].

Practical Implication

The average regular WU is more likely to be the ideal WU for NCAA Division 1 swimmers. However, no WU or a short WU may benefit up to 50% of these swimmers. A variety of WU variations is necessary to determine which WU is ideal for 50-yard performance, as one would expect the fastest time with their accustomed WU, no matter the distance. These findings are extremlely interesting, as many coaches wonder about an ideal WU protocol if no WU pool is available. For some swimmers, no WU pool may maximize performance. 

In the future, out of water dynamic stretching protocols should be compared, as it seems 5 - 10 minutes of dynamic stretching improves running performance, swimming studies are needed (Turki 2011).
References
  1. Balilionis G, Nepocatych S, Ellis CM, Richardson MT, Neggers YH, Bishop PA. Effects of different types of warm-up on swimming performance, reaction time, and dive distance. J Strength Cond Res. 2012 Dec;26(12):3297-303. doi: 10.1519/JSC.0b013e318248ad40.
  2. 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. 
By Dr. G. John Mullen received his Doctorate in Physical Therapy from the University of Southern California and a Bachelor of Science of Health from Purdue University where he swam collegiately. He is the founder of Mullen Physical Therapy, owner of COR PT, Strength Coach Consultant, Creator of the Swimmer's Shoulder System, and chief editor of the Swimming Science Research Review.

Warm-up Muscle Temperature


We and other sources have written extensively about warm-up (WARM-UPS SHOULD MATCH INTENDED PERFORMANCE INTENSITYSPRINT PERFORMANCE IMPAIRED BY TOO MUCH/INTENSE WARM-UP'Perfect' Swimming Warm-up). Most of these pieces have suggested too much warm-up may impair performance and an individualized warm-up program is most appropriate, as different swimmers require different length warm-ups. 

To determine an appropriate warm-up length and intensity, it is often suggested to perform different warm-ups at practices or local meets. While this is a practical suggested, many unaccounted variables still exist. For instance, the air and water temperature at the meet, length of time between events, availability of warm-up and pools, etc. 


For these complications, a more objective measure is likely ideal for measuring pre-race preparation. Exercise performance has been correlated with muscle temperature in the past. Increasing the heat of the muscle is one of the mechanisms behind performing warm-up activities. In sprinting events, it muscles receive greater benefit from an increase in muscle temperature. To accommodate this theory, it has been suggested sprinters should warm-up greater lengths to illicit this increase in muscle temperature. Endurance athletes are commonly suggested not to perform longer warm-ups as may deplete glycogen levels and cause thermodynamic strain, impairing endurance performance. The most common methods to increase muscle temperature are through an active warm-up, but the use of external aids to enhance muscle temperature may provide the beneficial effects of a heated muscle, without the residual downsides (depleted glycogen or thermodynamic strain). 

Faulkner 2013 noted a 9% improvement during a 30-second sprint cycling bout noted with a 1 degree centigrade increase at the depth of 1 - 4 cm. This increase in temperature likely increases the force-velocity of fast- and slow-twitch muscle fibers. Moreover, ATP has been suggested to increase in heated conditions. It is possible that the increase in blood lactate concentrations is due to the vasodilation associated with heating. 

Now, measuring the temperature of muscle under the skin is not currently feasible, as needle thermistor probes are the common method in research, but finding a simple, reliable method of measuring muscle temperature doesn't seem too far away. 

Practical Implication
Measuring muscle temperature may be a method of measuring warm-up efficiency in the future. However, simply warming-up the muscle will not likely result in the best warm-up. Each swimmer should have an individualized warm-up, designed to warm-up the muscles, as well as prepare the body for future movements.

Related Reading
  1. Faulkner SH, Ferguson RA, Gerrett N, Hupperets M, Hodder SG, Havenith G. Reducing Muscle Temperature Drop after Warm-up Improves Sprint Cycling Performance. Med Sci Sports Exerc. 2013 Feb;45(2):359-65. doi: 10.1249/MSS.0b013e31826fba7f.
By Dr. G. John Mullen received his Doctorate in Physical Therapy from the University of Southern California and a Bachelor of Science of Health from Purdue University. He is the founder of Mullen Physical Therapy, the Center of Optimal Restoration, head strength coach at Santa Clara Swim Club, creator of the Swimmer's Shoulder System, and chief editor of the Swimming Science Research Review.