# How accurate is your Garmin’s VO2max estimate?

Traveling along the trails, sidewalks, and main streets of the towns they reside in, runners, cyclists, and endurance sports athletes everywhere all know a familiar sound. The delightfully gratifying chirp of a fitness tracker as you complete your next mile, achieve a new PR (personal record), or record a new VO2max.

Ever since I entered the world of endurance sports training eight years ago, I’ve heard athletes talking about their VO2 max, how to improve it, and how accurate (or not?) fitness trackers are at actually measuring these values.

I decided to explore the technology of Garmin fitness watches to understand how VO2max is calculated and do a baseline comparison of how these wearable technologies VO2max predictions compare to laboratory testing.

Firstbeat Technology’s Fitness Test is used by Garmin and other fitness companies to calculate VO2max for a variety of different activities. Described in patent US20110040193A1, this Fitness Test calculates users’ VO2 in the following steps:

1) The personal background info (at least age) is logged
2) The person starts to exercise with a device that measures heart rate and speed
3) The activity collected data is segmented to different heart rate ranges based off the persons background info and the reliability of different data segments is calculated(reliability is measured based off how continuous the activity is- uninterrupted segments are better than those where the user has to stop)
4) The most reliable data segments are used for estimating the person’s aerobic fitness level (VO2max) by utilizing the person’s heart rate and speed data

Speed data from reliable segments are used to calculate a VO2, oxygen consumption, during that segment. 20-30s bouts are used to calculate VO2 across segments using one of the following theoretical VO2 calculations:

Walking and Pole Walking: Theoretical VO2 (ml/kg/min)=1.78*speed*16.67[tan(inclination)+0.073]
Running on a Level Ground: Theoretical VO2 (ml/kg/min)=3.5 speed
Running in a Hilly Terrain: Theoretical VO2 (ml/kg/min)=3.33*speed+15*tan(inclination)*speed+3.5
Cycling: Theoretical VO2 (ml/kg/min)=(12.35*Power+300)/person’s weight
Rowing (Indoor): Theoretical  VO2 (ml/kg/min)=(14.72*Power+250.39)/person’s weight                                Unit of speed=kilometers per hour (km/h)
Unit of inclination=degrees)(°)
Unit of power=watts (W)
Unit of weight=kilograms (kg)

From these calculated theoretical VO2 values, heart rate information is used to determine effort of segments. Heart rate zones based on user information are utilized to evaluate effort, and then effort is used to determine that VO2 as a %VO2max. VO2max estimates are made for each segment using %VO2max. These segment VO2max can be weighted based off heart beat derived parameters and performance parameters, and then used to calculate VO2max.[1]

An affordable mode of tracking your VO2max through measuring heart rate and speed data – pretty neat, right? But how accurate is this technology and how does it match up to laboratory testing?

Firstbeat conducted their own study to validate the technology and its effectiveness at estimating VO2max. They found that “[t]he accuracy of the method when applied for running is 95% (Mean absolute percentageerror, MAPE ~5%), based on a database of 2690 freely performed runs from 79 runners whose VO2max was tested four times during their 6-9 -month preparation period for a marathon”(4). Error in estimated VO2max was less 3.5ml/kg/min in most cases, which is fairly accurate considering most submaximal testing has an error of 10-15%. Method accuracy varied with respect to estimated maximum heart rate(HRmax). ” If the HRmax is estimated 15 beats/min too low, the error in the VO2max result is about 9%. Respectively, if the HRmax is estimated 15 beats/min too high, the error in VO2max result is 7%. If the person’s real HRmax is known, the VO2max assessment error falls to the 5% level”(5). This study suggests a high degree of accuracy for Firstbeat’s fitness test technology in predicting VO2max.[2]

A group of scientists at Southern Illinois University Edwardsville evaluated the wearable technology’s accuracy by conducting a laboratory VO2max test on male and female runners, then allowing participants to use the wearable technology to calculate VO2max in a 10 minute self guided run. They found that the Garmin Forerunner 230MAX and 235MAX measured VO2max within -0.3 ± 3.4 ml/kg/min, p=0.02 for the 230MAX and -1.1 ± 4.0 ml/kg/min, p=0.026 for the 235MAX for female runners, and -1.1 ± 3.4 ml/kg/min, p=0.149 for the 230MAX and -3.2 ± 4.2 ml/kg/min, p=0.002 for the 235MAX for male runners. There is a greater amount of variability in the male group; however, this could be due to miscalculations in HRmax and potential variations in levels of effort in participant during the 10 minute self guided run. Although there is greater variability within the male group, the devices still appear fairly accurate at predicting VO2max.[3]

Wearable conducted an evaluation of their own putting fitness watches to the test – assessing the accuracy of Garmin, Fitbit, and Jabra devices in measuring VO2max. They found that Garmin technology provided a VO2max estimation within 0.3 ml/kg/min of their study participant, which was the most accurate of all devices tested. The high degree of accuracy found in their study remains consistent with other larger scientific studies.[4]

Across the board, there appears to be a high degree of accuracy with Firstbeat’s Fitness Test in estimating VO2max. For endurance athletes everywhere, this is a huge sigh of relief. Rather than partaking in expensive, strenuous VO2max testing, we can monitor our progress utilizing the technology in the watches we wear everyday. In addition to watching our paces, heart rates, and overall progress, we can also monitor our cardiovascular health and athletic progress as we continue to train and push ourselves everyday.

References:

[1]Seppanen, M., Pulkkenin, A., Kurunmaki, V., Saalasti, S., & Kettunen, J. (2016). U.S. Patent No. US20110040193A1. Washington, DC: U.S. Patent and Trademark Office

[2] Firstbeat Technology(2014). Automated Fitness Level (VO2max) Estimation with Heart Rate and Speed Data.

[3]Snyder, N. C. , Willoughby, C. A. & Smith, B. K. (2017). Accuracy of Garmin and Polar Smart Watches to Predict VO2max. Medicine & Science in Sports & Exercise, 49(5S), 761. doi: 10.1249/01.mss.0000519024.10358.0b.

# Can You Beet The Competition With Nitrate Supplements?

Nitric Oxide (NO) is a supplement currently used by many athletes because it is a known vasodilator, which can increase blood flow, mitochondrial efficiency, and contractility of muscles. While there are a few different kinds of nitrate supplements, the most common comes in the form of beetroot juice. When ingested, the nitric oxide is easily broken down into nitrate, which can be used by the body to help increase efficiency of exercise. Multiple studies have been done regarding the effect of beetroot juice supplementation in both trained and untrained athletes; as well as by acute or long term dosing. Due to the nature of NO in exercise, it is generally used to supplement endurance activities, with only a few studies looking at shorter length, or strength exercise. Currently, there is data to suggest that beetroot juice has a more noticeable effect in untrained individuals than in trained athletes, which is not surprising. The trend normally seen in these studies is that acute doses of beetroot juice will lower VO2 during submaximal exercise, allowing individuals to exercise more efficiently. Another effect of nitrate is the increase in mitochondrial efficiency. This effect was tested through long term studies regarding beetroot juice supplementation. In low-moderately trained athletes it was also found that VO2 decreased at submaximal exercise, similar to acute dosing. Additionally, exercise tolerance was also increased by up to 16% after one week of supplementation. While this may be due to the effects of training it was a significant difference. In highly trained athletes, it was found that beetroot juice increased workload and reduced energy cost at exercise intensity. However, the variability in performance could have been the cause of this as noted by the authors of the study. Overall, while there is some evidence to support the use of beetroot juice as an ergonomic aid, there is also a large amount of data to suggest that it has very little to no effect of athletic performance.

Table of studies done to research the effects of acute nitrate supplementation in elite athletes

This topic relates to class in that it aims to determine what affect different training methods/supplements have on athletic performance. It seems that there are potential benefits to using beetroot juice or other nitrate supplements as a training tool in both acute and long-term doses. One of the issues seems to be in determining the proper dosage of beetroot juice. There were multiple studies where no benefit was seen with small doses and significant benefits were seen with a higher dose. Determining this value will be important in future studies to ensure that possible benefits are not being overlooked. Additionally, larger studies should be conducted as only one study referenced in the article had more than 20 subjects. This could be a potential major limitation given the large amount of variability in and between different athletes and sports. NO supplements also would seem to be more beneficial to endurance athletes than it would be to strength athletes during training. While there is only a small amount of evidence to support the claim that beetroot juice will improve athletic performance, there is no data to suggest that taking this supplement will have negative effects on performance so trying it in your next training cycle may be worth it.

References                                                                                                                         Andreas Zafeiridis. The Effects of Dietary Nitrate (Beetroot Juice) Supplementation on Exercise Performance: A Review. American Journal of Sports Science. Vol. 2, No. 4, 2014, pp. 97-110. doi: 10.11648/j.ajss.20140204.15

# Muscle Stretch Shortening in Upper Extremity Explosiveness

After talking briefly about muscle stretch shortening in class, I thought this was an interesting topic and looked into some literature to better understand what is going on. I found a study that focused on upper-body explosive movements, and how load and stretch shortening cycles (SSC) affect the kinematics, kinetics, and muscle activation that occur. This was an interesting study because they looked at maximal effort bench throws, where much of the previous research focused only on lower-extremity exercises. Each subject performed an SSC throw and concentric only throws, comparing displacement, velocity, acceleration, force, power output and EMG from the pectoralis major, anterior deltoid, and triceps brachii. SSCs are usually performed before explosive movements (e.g. throwing, jumping) which lengthen the muscle preparing to contract to ensure maximal velocity is reached during the movement. When the muscle lengthens, elastic energy is stored which can then be released during the movement, however, if the time between lengthening and contracting is too long, the energy dissipates, leading to a slower contraction with less power.

As expected, the average velocity was lower for the concentric only throws when compared to the SSC throws, however, there was no difference in throw height between the two groups. Average and peak force and power output were both higher for the SSC through compared to the concentric only throw. The findings from this study agree with findings from previous studies focusing on vertical jump, showing that similar muscle kinetics are at play. Muscle kinetics are an extremely interesting area of study, and even though we only briefly discussed muscle length-tension, force-velocity, and power relationships in class, this is a huge field of study. Some groups choose to look at specific muscle groups, while others look at more complex movements that require multiple groups of muscles to be activated. This area of research has led to improvements in stretching suggestions for athletes; stretching before performing explosive movements is not actually as beneficial as we once thought. Stretching the muscle allows for elastic energy dissipation, instead of storing the energy for immediate release. However, stretching is still extremely beneficial after workouts, helping to prevent muscle soreness and excess inflammation. Additionally, there are some chronic adaptations to stretching including increasing flexibility for a wider range of motion during typical daily activities as well as athletic endeavors.

References:

1. Newton, R. U., Murphy, A. J., Humphries, B. J., Wilson, G. J., Kraemer, W. J., & Häkkinen, K. (1997). Influence of load and stretch shortening cycle on the kinematics, kinetics and muscle activation that occurs during explosive upper-body movements. European Journal of Applied Physiology and Occupational Physiology, 75(4), 333–342. https://doi.org/10.1007/s004210050169
2. Bosco, Carmelo, and Paavo V. Komi. (1979) Mechanical characteristics and fiber composition of human leg extensor muscles. European journal of applied physiology and occupational physiology4 (1979): 275-284.

# Muscle Fiber Composition In Competitive Powerlifters

Yesterday, I came across a paper focusing specifically on power lifters and how their muscle fiber compositions compare to sedentary counterparts. The study took vastus lateralis biopsy samples from 5 competitive power lifters, and 5 sedentary participants. Muscle fiber compositions were determined using MTPase histochemical analysis. Interestingly, it was found that sedentary participants expressed 12% type 2B fibers, while power lifters expressed an 11-percent decrease to 1% type 2B. Conversely, power lifters expressed 45% type 2A fibers compared to the sedentary group’s 33%.

Recently in class, I had the opportunity to present on another paper that studied the correlation between muscle fiber composition and obesity. The results found that there was a positive correlation between muscle type 2B fibers and BMI. Obese patients expressed 18% type 2B fibers, significantly more than their lean counterparts. The apparent increase in fiber type 2B expression in obese people compared to an apparent decrease in expression of type 2B in power lifters engenders questions as to the reasons behind the shifts.

This seems to communicate that the training, genetic make-up, or both of the competitive power lifters population appears to encourage more type 2A fast-twitch fibers compared to type 2B. The study was limited to groups of n=5, and would likely be greatly informed with an increased sample size. Additionally, a longitudinal study following the muscle fiber composition of individuals proceeding from novice to competitive power lifting could help isolate the effects of training of relative fiber type2A/B compositions.

1. Fry, A. C. et al. Muscle fiber characteristics of competitive power lifters. J. Strength Cond. Res. 17, 402–410 (2003).
2. Tanner, C. J. et al. Muscle fiber type is associated with obesity and weight loss. Am. J. Physiol. Metab. 282, E1191–E1196 (2002).

# Epigenetic Muscle Memory

What comes to mind when I hear the term muscle memory is the typical example being able to ride a bike with ease even if you haven’t ridden one in a long time.  This time of memory is neurologic and comes from repetition of motor tasks. It primarily involves the dorsolateral premotor cortex and cerebellum.[1] However, there is a different kind of muscle memory that a recent study just discovered a lot about.[2] This muscle memory is referring to epigenetic changes to the DNA of human skeletal muscle.

Epigenetics is changes that affect gene expression without altering the DNA sequence but instead turn on and off specific genes. Three ways that genes can be silenced are DNA methylation, histone modifications, and RNA-associated silencing.[3] DNA methylation is what plays a key role in muscle memory and is a major part of the study.  It is a chemical process of adding a methyl group onto DNA that only occurs where cytosine and guanine nucleotides are next to each other and the guanine is linked to a phosphate.[2] This is referred to as a CpG site.

This study used 8 healthy males with no previous training. They went through three phases: loading, unloading, and reloading. Whole-body DEXA and vastus lateralis muscle biopsies were taken at baseline and at the end of each phase. Over 850,000 CpG sites were investigated. Many genes where found to be hypomethylated and showed increased gene expression. This epigenetic memory of earlier muscle growth means that at a later time there can be a greater response to exercise and more muscle growth.

As a person who has encountered many injuries and been forced to take multiple weeks off from the gym, it is comforting to know that despite the loss in strength that occurs during the time off my muscles will hold this memory and be more capable of regaining it.

One possible major implication of this study is a change in bans due to performance enhancing supplements, as this could mean the effects may be much longer lasting. Should people caught using them ever get to return to their sport knowing this? More research needs to be done on this specifically before real decisions can be made on this but it is definitely a future path for this research

[1] Robb T. How to play like a pro: The neuroscience of muscle memory. Oxford Neurological Society. http://neurologicalsociety.org/play-like-pro-neuroscience-muscle-memory/. Published 2016. Accessed March 14, 2018.

[2] Seaborne RA, Strauss J, Cocks M, et al. Human Skeletal Muscle Possesses an Epigenetic Memory of Hypertrophy. Sci Rep. 2018;8(1):1898. doi:10.1038/s41598-018-20287-3.

[3] Simmons, D. (2008) Epigenetic influence and disease. Nature Education 1(1):6

[4] Improving your Muscle Memory – Making Good Technique Automatic. National Federation of State High School Associations. https://www.nfhs.org/articles/improving-your-muscle-memory-making-good-technique-automatic/. Published 2014. Accessed March 14, 2018.

[5] Sharples AP, Stewart CE, Seaborne RA. Does skeletal muscle have an “epi”-memory? The role of epigenetics in nutritional programming, metabolic disease, aging and exercise. Aging Cell. 2016;15(4):603-616. doi:10.1111/acel.12486.

# Sweating on Ice: Jocelyne Lamoureux-Davidson’s Historic Win for Team USA

With the 2018 Winter Olympics coming to a close, I thought it would be pertinent to discuss one of the most ground-breaking wins for team USA. Last week, the U.S. Women’s Ice Hockey team beat Canada 3-2 in a shootout for the gold medal. The U.S. Women’s team has only won gold once before, in 1998, so this is certainly a win that will go down in history. The team all put in a tremendous effort for the win, but Jocelyne Lamoureux-Davidson, the player that scored the game-winning shot, has become somewhat of an American hero.

As the entire world watched on, Lamoureux Davidson was faced with one of the most high-stakes games of her life. It was all up to her. Now, I don’t know about you, but I get stressed out for something as small as a class presentation or final exam. Her (and the rest of the team’s) ability to work through and cope with extreme stress is truly remarkable. I know for a fact that if I were in that same position, I would certainly crumble.

Figure 1. Jocelyne Amoureux-Davidson playing for Team USA in 2017

Perhaps one of the most profound differences between elite athletes and everyday people is the ability to manage stress, both long and short-term. Most people would recognize the concept of “fight or flight,” that describes the body’s physiological response to stressful situations, or “threats.” This response originally served as a survival mechanism, protecting early humans from life-threatening risks like animal attacks, but people may experience the same stress response to family issues, work, or in this case, hockey shootouts.

The physiological responses to stress are dictated by the sympathetic and parasympathetic nervous system. Perceived threats prompt the sympathetic nervous system to release a cascade of several different hormones and eventually cortisol, a steroid hormone, that keeps the body on high alert. It gives the body an extra burst of energy that can allow the person to either combat the threat (fight) or run away (flight). When the coast is clear, the parasympathetic nervous system is activated to dampen the effects of the hormones.

While it is interesting to study the short term effects of cortisol, some of its most intriguing effects occur in the long-term. Because athletes are constantly faced with high-stress situations, they may experience the effects of chronic stress, including anxiety, insomnia, high blood pressure, and weakened immune system. After years of training and competing, athletes often experience “burnout,” which has the potential to end their high-stress career. In a study published in Psychology of Sport and Exercise in 2016, investigators examined the key factors that contributed to the stress-burnout relationship. It was found that both athlete resilience and coach social support played a crucial role in the moderation of stress and maintenance of psychological health.

After a win, many athletes will take the time to thank their friends, family, and coaches. This may just seem like a nice gesture, but it is scientifically supported that their support can contribute to the athlete’s success. In such a high-stress environment, it is imperative that athletes have access to a support system to help cope with the constant flow of cortisol. Lamoureux Davidson’s coach must be proud.

1. “U.S. Women Golden at 2018 Olympics” (2018) by USA Hockey, http://teamusa.usahockey.com/news_article/show/889602?referrer_id=695820
2. Figure 1. Attribution: BDZ Sports [CC BY-SA 4.0 (https://creativecommons.org/licenses/by-sa/4.0)], via Wikimedia Commons
3. “Understanding the Stress Response” (2011), https://www.health.harvard.edu/staying-healthy/understanding-the-stress-response
4. “Understanding Chronic Stress” (2018), http://www.apa.org/helpcenter/understanding-chronic-stress.aspx
5. F.J.H Lu, et. al. “Interaction of athletes’ resilience and coaches social support on the stress-burnout relationship: a conjunctive moderation perspective” Psychology of Sport and Exercise (2016) Vol. 22, pp. 202-209

# “Eleven Wretched Women”

The media often puts their own spin on the news in order to make a statement or point of some sort. After reading Chapter 5 of David Epstein’s The Sports Gene, it is apparent that this can be traced back all the way to the 1928 Olympic Games in Amsterdam (Epstein, 59-60). After the women’s 800m run in 1928, John Tunis of the New York Evening Post reported, “Below us on the cinder path were 11 wretched women, 5 of whom dropped out before the finish, while 5 collapsed after reaching the tape.” This reporting caused the International Olympic Committee to keep the 800m off the program until 1960. It was interesting that a simple news article was able to create this kind of power and able to change the Olympic Games.

I researched more about this specific race and came across this article (here), which reported the actual facts of that race. Roger Robinson, a senior writer for The Running Times, describes the race in detail, noting that there were actually only 9 runners in the race, as opposed to the 11 originally reported. Only one of them fell, and not from exhaustion, but instead because she was leaning forward to try to lean forward to beat her competitor. A photo of the winner was captured, Germany’s Lina (Karoline) Radke-Batschauer, in which she shows no signs of exhaustion.   According to Robinson, not only was this race false reported in the New York Evening Post, but in other newspapers as well. For example, newspapers said that women’s reproductive capability impaired by such “terrible exhaustion.” England’s Daily Mail affirmed that women who raced longer than 200m would age prematurely.

The fact that these reports were able to convince the IOC that the women’s 800m should no longer be a part of the Olympic Games shows what kind of influence the media has on our culture. It banned the 800m for over 30 years, simply because these reporters thought that women couldn’t handle such a race. Even in 1967, when the first woman ran in the Boston Marathon, she received a lot of criticism and disbelief, with people saying that there was slim to no chance that she would be able to win (read more about her experience here). It is shocking that people’s opinions can influence the rules of sporting event so drastically. Today, with social media, this problem is even more prevalent than before. Opinions are publicized from many different parties, not only confusing people, but sometimes distributing incorrect information. When discussing the issue of nature versus nurture when it comes to athleticism, it is important to consider how the media has influenced opinions in the past and present, as it can cause some serious misconceptions.

Works Cited:

Epstein, David J. The Sports Gene: Inside the Science of Extraordinary Athletic Performance. 2014.

Robinson, Roger. “‘Eleven Wretched Women.’” Runner’s World, 16 May 2017, www.runnersworld.com/running-times-info/eleven-wretched-women.

Switzer, Kathrine. “Boston, 1967: When Marathons Were Just for Men.” BBC News, 16 Apr. 2012, www.bbc.com/news/magazine-17632029.

# How Uniforms Influence Speed Skating Performance

With the Winter 2018 Olympics in full swing, it is easy to get caught up analyzing an athlete’s performance, from the routine to the costume. Of course costumes are meant to attract all of attention to the individual wearing them, but could there possibly be another, more scientific, reason for wearing these eye catching get-ups? The Washington Post recently put out an article that goes to answer this question. “In the Olympics, what athletes wear is often more about science than style,” by Rachel Feltman, explores the motivation behind uniforms worn by speed skaters.

This article looks at various factors related to costuming which may play into how a speed skater performs during a race. Comfort and personal preference of one color over another were two aspects of the costume that played a role in an individual’s performance. If the skater was comfortable and believed that they would shave a few seconds off their time in a blue suit rather than a red suit, time would actually improve. This points back to the belief that the mind has the ability to elevate an athlete’s skills or performance based on how they think they should be operating.

There is more to speed skating though than just the color of the costume, skill of the athlete, and comfort of the suit. As the individual skates across the ice, they are experiencing a considerable drag from the air. While air does not create as great of a drag force on speed skaters as water creates on swimmers, it could be the deciding factor between which athlete receives gold and silver due to the milliseconds this force costs the athletes. For this reason, countries have invested time and money into researching a uniform that would not only be stylish and comfortable, but also aerodynamic. In 2014 Under Armour began to research the best possible combination, trying out over 250 combination of fabric. The final costume worked to make the skater as sleek as possible to reduce drag, used fabrics that would not create frictional forces as the skater’s thighs rubbed together, and was dotted with tiny bumps to allows the skater to fly across the ice, similar to how a golf ball speeds through the air.

This article relates directly back to the topics covered in this course because it looks at how engineering principles influence the sports world. It looks at topics such as reducing friction, making the athletes more aerodynamic, and showcases how much time and energy goes into creating these products.

It is interesting to see how costumes influence an athlete, and begs the question as to whether or not there are other facets of uniform design which would be optimized to increase performance. Aerodynamics and friction have both been explored in this article, but could there be others as well?

Works Cited:

Feltman, R. (2018, January 21). In the Olympics, what athletes wear is often more about science than style. Retrieved February 19, 2018, from https://www.washingtonpost.com/lifestyle/kidspost/in-the-olympics-what-athletes-wear-is-often-more-about-science-than-style/2018/01/19/67626414-f6ce-11e7-a9e3-ab18ce41436a_story.html?utm_term=.a1979b18e25b

# Sports Specialization in Young Athletes: Evidence-Based Recommendations

In a review published in Sports Health, Neeru Jayanthi discusses the evidence for and against sports specialization in young athletes, specifically those under the age of 12. He begins by defining sport specialization as intense, year-round training in a single sport with the exclusion of other sports. He then compiles a table that succinctly displays the results of his literature review. He has reviewed 12 studies, in which he has identified the type of sport, type of athletes involved in the study, age at which they began their training of the sport, and the age at which they specialized. With the exception of two studies, both of which studied rhythmic gymnastics, the studies showed that most elite athletes had diversified early and specialized after 12 years of age. He goes on to discuss other factors that may impact success in sports, such as personal enjoyment of the sport and self-motivation. Lastly, he discusses how injury and burnout may be a result of high-intensity training. He concludes by stating that some specialization is needed to attain elite-level skills, however, it should be delayed until late adolescence to minimize injury and burnout.

This is a similar conclusion that was drawn by David Epstein in The Sports Gene. He too seems to conclude that early specialization may be harmful instead of beneficial to children aiming for elite status in a sport. He agrees that some sports do require early specialization, such as gymnastics, but that is only because they are able to perform at this elite level before they go through puberty. Otherwise, based on the studies he has reviewed, it doesn’t seem required to attain this level (Epstein, 51-52).

I agree with the conclusions drawn from both Jayanthi’s review, as well as Epstein’s. Early diversification allows for children to gain experience in multiple sports, allowing them to acquire skills that may be beneficial. Just like it is encouraged for students to study many different subjects in order to work both sides of their brains, and to be well-rounded students, the same can be said for athletes. Not only does diversification prevent burnout and injuries, but perhaps it could possibly aid the athlete in seeing the sport in a new way, eventually taking what he or she has learned from previous sports and applying it to their specialized sport. Even certain professional athletes today didn’t specialize until much later, if ever. For example, Danny Ainge, who is currently the general manager for the Boston Celtics, is the only player to be named a high school first team All-American in football, basketball and baseball. He then went on to play basketball at Brigham Young University, where he also played professional baseball for three seasons with the Toronto Blue Jays. After, he went on to play for the Celtics. There are other players like him, who were double or even triple sport college athletes. Did not specializing hurt their careers? Or did it help them? Could they have been even better at one sport if they had specialized? I like that this article also took into account (briefly) motivation and enjoyment of the sport. That isn’t something that has been discussed in the book yet, and I am excited to see what Epstein has to say about it.