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Strength Training for Triathletes:
Blending Anecdotal and Empirical Evidence to Improve Triathlon Performance
by
Kevin J. Le
A THESIS
submitted to
Oregon State University
Honors College
in partial fulfillment of
the requirements for the
degree of
Honors Baccalaureate of Science in Kinesiology
(Honors Scholar)
Presented June 4, 2018
Commencement June 2018
2
3
AN ABSTRACT OF THE THESIS OF
Kevin J. Le for the degree of Honors Baccalaureate of Science in Kinesiology presented
on June 4, 2018. Title: Strength Training for Triathletes: Blending Anecdotal and
Empirical Evidence to Improve Triathlon Performance.
Abstract approved: Erica McKenzie
Triathlon is an endurance sport consisting of back-to-back swimming, cycling, and
running. There are four popular distances: sprint (.75km swim, 20km bike, 5km run),
Olympic (1.5km swim, 40km bike, 10km run), half-ironman (1.9km swim, 90km bike,
21.1km run), and ironman (3.8km swim, 180km bike, 42.2km run). Even at the shortest
distances, elite triathlon performance requires excellent aerobic fitness (maximum rate of
oxygen consumption and lactate threshold) and movement economy.1 Strength training,
defined here as weight lifting targeted at primary movers of large muscle groups, is
becoming popular as a means of improving performance. Empirical evidence shows
heavy strength training to benefit endurance sport performance in laboratory settings.
However, optimal training changes in the context of confounding variables of life, such
as family and work, and the additional stress they create. The purpose of this project is to
explore both the scientific and unscientific elements of triathlon training to aid triathletes
in developing a plan for strength training (or none at all) to improve their performance.
Key Words: strength training, resistance training, weight lifting, triathlon
Corresponding e-mail address: [email protected]
4
©Copyright by Kevin J. Le
June 4, 2018
All Rights Reserved
5
Strength Training for Triathletes:
Blending Anecdotal and Empirical Evidence to Improve Triathlon Performance
by
Kevin J. Le
A THESIS
submitted to
Oregon State University
Honors College
in partial fulfillment of
the requirements for the
degree of
Honors Baccalaureate of Science in Kinesiology
(Honors Scholar)
Presented June 4, 2018
Commencement June 2018
6
Honors Baccalaureate of Science in Kinesiology project of Kevin J. Le presented on June
4, 2018.
APPROVED:
_____________________________________________________________________
Erica McKenzie, Mentor, representing Carlson College of Veterinary Medicine
_____________________________________________________________________
Sean Newsom, Committee Member, representing College of Public Health and Human
Sciences
_____________________________________________________________________
Aaron Seipel, Committee Member, representing College of Public Health and Human
Sciences
_____________________________________________________________________
Toni Doolen, Dean, Oregon State University Honors College
I understand that my project will become part of the permanent collection of Oregon
State University, Honors College. My signature below authorizes release of my project
to any reader upon request.
_____________________________________________________________________
Kevin J. Le, Author
7
Acknowledgements
Thank you to my mentor and OSU Triathlon Club coach, Erica McKenzie, for giving me
both independence and guidance during the journey of writing this thesis.
Thank you to Jay Penry for being an excellent instructor and finding time to discuss my
thesis and tangents, such as cycling, endurance training, and ways I can further my
education at OSU.
Thank you to Sean Newsom for also being a great professor and stepping in last second
to listen to my defense.
Last but not least, thank you to Aaron Seipel for being a great friend, roommate, training
buddy, competitor, motivator, and someone I can complain to about almost anything.
And… thank you to Blair Bronson, Staci Partridge, and the rest of Oregon State Triathlon
for being a second family to me.
8
Table of Contents
Preface ………………………………………………………………………………… 9
Introduction …………………………………………………………………………... 9
Challenges of Triathlon ……………………………………………………………… 11
Time 12
Energy: The Stress Budget 12
Limitations of Science 15
Individuality 17
Strength Training Physiology and Benefits ………………………………………… 19
Physiological Demands of Triathlon Performance 19
Basic Muscle Physiology 19
Strength Training and Endurance Performance in Trained Individuals 22
Injury Rehabilitation and Prevention 24
General Health 25
Art: A Balancing Act ………………………………………………………………… 26
If Strength Training is Desired: How-To …………………………………………... 28
Summary ……………………………………………………………………………... 33
Decision-Making Flowchart ………………………………………………………… 34
Guidelines for Levels of Focus ……………………………………………………… 35
References ……………………………………………………………………………. 38
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Preface
All opinions in this text are products of personal knowledge and experience with
triathlon, both of which stem from several years of training, racing, coaching, and
education (undergraduate Kinesiology degree and self-guided reading). This is not an
assertion of personal views as golden rules; they are only personal. However, read with
an open mind, and this text may lead to seeing something in a different light and new
realizations.
Introduction
This text is intended to be a discussion about strength training for triathletes.
Here, strength training is defined as weight lifting to increase maximum force production
and rate of force production within major muscle groups. Strength training does not refer
to rehabilitative exercises like those found in physical therapy programs. This text
reviews current scientific literature related to strength training and endurance sport
performance, but it also considers abstract elements of triathlon that are not able to be
evaluated in randomized controlled trials. It includes significant influence from
practice—the art of coaching, training, and racing—and anecdote, two unscientific but
important and highly-prevalent forces in endurance sport training and racing. This text is
not a formal scientific review nor does it propose there is a single best way to strength
train for triathlon. There are no example strength training programs included in this
document, as there are plenty of free or inexpensive resources with adequate weight
lifting routines. This work does include, however, guidelines on how to approach strength
training, how much energy to put toward strength training, and general goals for different
10
levels of strength training. Through a combination of the abstract elements of triathlon
training and scientific principles, this text is intended to inform athletes how they might
take their personal needs into consideration in deciding what role strength training can
play in their athletic pursuits.
Triathlon is a young sport full of contradictory opinions on how to optimize
performance on race day. Because of its time demands and its complex nature as a
combination of three sports, training can be considered as much of an art as it is a
science. It can be argued other endurance sports are more informed by science due to
greater simplicity (training a single sport vs. three) allowing for more applicable
experimental results; however, it is difficult to apply the results of traditional research
trials to triathlon with great validity because of the following factors. Research
experiments take place in controlled laboratory settings with controlled variables and
often reveal distinct, objective outcomes. However, countless variables impact both
training and race-day performance for triathletes, and these interactions are impossible to
dissect. For example, how does a high volume of run training impact the athlete’s ability
to swim with proper technique? How does a subsequent bike workout after a run workout
impact the potential adaptations that would follow an isolated run workout? Does
replacing a swim/bike/run session with a strength training session yield better
performance on race day? There are certainly no clear answers to these questions, and the
answers likely differ between individuals.
The umbrella question governing all decisions related to optimizing training is:
“What should I do right now to maximize my performance on race day?” Under this
question falls many more specific questions. Some of them, related to this text, include
11
should I do more swim/bike/run volume or intensity? Is more always better? Should I lift
weights, and how should I lift weights? Should I lift weights in addition to my endurance
training or in place of a portion of it? Should I train through tiredness and fatigue, or
should I rest? This text will demonstrate how much the answers to these questions can
vary and are dependent on wide range of factors. The individual’s path to optimal athletic
performance constantly changes with the confounding factors of everyday life. For
example, a period of illness or injury alters the optimal sequence of workouts leading up
to a race, or a few stressful weeks at work impacts personal motivation and changes the
best path to maximum performance. Hopefully, reading this text will help athletes to
think about their training and to create a plan for strength training suited to their own life.
Challenges of Triathlon
The individualism of triathlon training is rooted in the challenges posed by the
need to be competent in three sports. Training three sports simultaneously creates
questions on how to budget time and energy. It also creates uncertainty in how training
should be structured due to the impacts of prior workouts on subsequent training within
and between days. There is minimal scientifically-based information to direct the
organization of training three sports to yield optimal adaptation and performance. The
unlimited possible combinations of discipline and duration introduce countless variables,
which are impossible to test in a controlled laboratory setting. There are so many
technical skills and elements of fitness that can be developed in triathlon training that this
becomes a large balancing act, consisting of working on weaknesses, capitalizing on
strengths, and preparing to race.
12
Time
A survey of 83 elite triathletes and 25 coaches provides insight into how much
elite triathletes train. The athletes in this study averaged approximately 25 km/week of
swimming, 305 km/week of cycling, and 80 km/week of running (Fernandez, Acero,
Lopez, & Pereiro, n.d.). While the authors did not record duration of training, it is
estimated the total time to complete these distances would be 25-30 hours per week (7
hours for swimming, 15 hours for cycling, 7 hours for running). The elite athletes
achieved peak volumes of over 40 km/week of swimming, 470 km/week of cycling, and
100 km/week of running (with peaks for each sport occurring on different weeks). On the
contrary, age-group triathletes with full-time employment and other life commitments
may average only 12-13 hours of training per week.
Retrospective studies show a large majority of elite endurance athletes achieving
superior results by adopting a polarized training regimen with about 80% of training
performed at low intensities and 20% at high intensities (Stöggl & Sperlich, 2015). For
the aforementioned elite triathletes, this means 20-25 hours a week are dedicated to low
intensity training. Age-group triathletes come nowhere close to these training volumes.
Thus, a potential limiter of performance for age-group triathletes is simply the time they
put toward training.
Energy: The Stress Budget
Fulfilling performance potential requires short-term and long-term mental and
physical fortitude. It requires an open mind and the desire to achieve confidence and
competence in every aspect of the sport. Colloquially, triathlon is said to be not a
13
destination, but a journey involving constant challenges that affect all areas of life. Jesse
Kropelnicki, founder and head coach of QT2Systems and a USA Triathlon coach of the
highest rank (Level III; achieved by less than 30 individuals in the USA), illustrates his
“stress budget” concept in lay articles and at USA Triathlon coaching clinics. The ‘stress
budget’ is the maximum amount of stress an individual can experience without it
becoming counterproductive to success as an athlete. It encompasses everything in life,
including employment, family, finances, and sport, and is very much related to time
availability. Stress is not inherently detrimental, because it is a stimulus for growth, but
there is only so much energy or effort that an individual can direct toward managing
stressors. Excessive stress results in burnout, demoralization, and, ultimately, regression
(J Kropelnicki, 2017).
Stress is dynamic and multifaceted with physical, mental, and emotional elements
all contributing to an end-product: short- and long-term performance in all areas of life.
In the context of triathlon training, strength training is an additional stressor composed of
the physical stress of lifting weights and the mental stressors related to traveling to the
gym, paying for a membership, fitting the workout into a schedule—thinking about an
entirely new item within a training program. The daily requirements of strength training,
such as commuting and completing the session, are short-term stressors. There is a
significant long-term stressor associated with strength training too; workouts must be of
quality and have consistency in order to provide optimal benefits. As with any kind of
goal-oriented practice, lifting weights every other month will not create effective
progress. Emotional stressors become relevant when the athlete starts to worry about
missing workouts or feels anxiety when making sacrifices to make time for strength
14
training. It is a balancing act: how much stress from various areas of life yields the best
triathlon performance.
One must also consider the individuality of perception of stress and distinguish
between absolute and relative stress. Training load quantification measures an absolute
stress, such as time spent training or miles run per week. However, 20 hours of training
(absolute stress) may be perceived as easy to an elite athlete, whereas the same amount of
training would be perceived as difficult to a beginner athlete (relative stress). Perception
of stress changes over time, as the beginner athlete may progress to an elite status and
now perceives a previous challenge as relatively easy.
Fortitude allows one to manage a large amount of stress, and differences in
fortitude between individuals helps govern how much stress they can cope with without
negative side effects. Those who succumb to small amounts of absolute stress will make
minimal progress, while those who effectively manage large amounts of absolute stress
will adapt and grow. Developing fortitude and resilience increases the size of the stress
budget.
To summarize, an athlete’s ability to manage stress determines the size of their
stress budget, and the size of the stress budget, along with its distribution between
stressors, determines the athlete’s potential for success. The individual who makes the
most efficient use of the largest stress budget has the greatest chance of achieving the
high level of performance they have prepared for.
15
Limitations of Science: Confounding Variables, Emotions, and Interactions between
Sports
Empirical evidence from randomized controlled trials (RCT) is an excellent tool
for designing effective training. Countless studies that have evaluated short term (several
weeks) adaptations to various kinds of workouts. Within endurance sports, for example,
high intensity training (HIT) yields greater improvements in VO2max and lactate
threshold than does sustained low intensity training (Milanović, Sporiš, & Weston, 2015).
In fact, a few sprints—totaling three minutes in duration—can provide the same
physiological benefits as hours of high volume low intensity training (HVLIT) (Gibala et
al., 2006). These results may suggest time is best spent training at high intensities, and
training at low intensities yields inferior results. Lay articles in particular tend to interpret
such experimental results
However, observational studies clearly show superior endurance sport
performances in individuals who accumulate massive amounts of time training at very
low intensities (Stöggl & Sperlich, 2015). Elite athletes spend thousands of hours over
the course of their careers at easy efforts.
It is impossible to have long-term longitudinal studies comparing an intensity-
based training plan to a volume-based training plan. Observational studies indicate it is
the years of accumulated low-intensity mileage that give elite athletes their physiological
capabilities (Seiler, 2010). Studies lasting 6 to 12 weeks will show relatively little
adaptation with HVLIT and much more adaptation with HIT, but they do not address the
sustainability of progress. They do not provide information regarding the long-term
effects of either, nor can they incorporate the mental and emotional components of hard
16
training. Will the high-intensity-induced adaptations continue to occur at week 24, or will
the athlete plateau and/or experience burnout by week 16? Does a HVLIT-based program
have great success due to the long-term sustainability of its associated mental, emotional,
and physical exertion?
Studies like that conducted by Gibala et al. occur in relative isolation of external
variables. The athletes’ training plans are standardized and closely monitored, and the
athletes are not training all three sports in multiple workouts per day. Such a study also
does not address the potential detrimental effects of maximal cycling intervals on
performing other workouts in a triathlete’s training regimen. Furthermore, in the real
world, the extrinsic motivation provided by the researchers in the laboratory does not
exist. Six weeks of sprint-based cycling workouts may yield superior results in the
laboratory, but they may also cause psychological burnout when performed on the living
room stationary bike due to the sheer discomfort of maximal effort. Sustainability is
crucial in real-world triathlon training and is achieved via a delicate balance of taxing and
restorative efforts. RCTs comparing various types of workouts simply do not address the
emotional and mental components of endurance training—they, by definition, cannot.
For example, an athlete experiences fatigue from performing frequent high
intensity bike workouts, and this fatigue interferes with his ability to swim with proper
body position. Even though his bike fitness may be optimized by such sessions, the
tradeoff with swim technique development may lead to non-optimal race day
performance. Consider an athlete who has poor cycling endurance and running speed.
Perhaps doing short, fast running intervals is the best possible way to improve the
athlete’s running ability. But if these intervals cause excess leg or central nervous system
17
fatigue and interferes with endurance-focused cycling workouts, another tradeoff must be
made.
Strength training has physical, mental, and emotional considerations like those of
swim/bike/run training. If an athlete strongly dislikes strength training, they will need to
draw on sheer willpower to deal with the time demands, discomfort, and physical effort
of lifting weights. This is likely unsustainable due to the transient nature of behavior
changes that draw from willpower, especially when the contribution of the behavior
change (strength training) to the outcome (race performance) is difficult to quantify
(Woolley & Fishbach, 2017). If the athlete enjoys lifting weights but has limited time for
additional training on top of existing swim/bike/run workouts, adding in regular strength
training sessions may be harmful if the stress budget is exceeded. Replacing a portion of
swim/bike/run with strength training might improve performance, but this topic has not
been well-researched in triathletes, especially in triathletes who are extremely time-
limited and are doing minimal amounts of swim/bike/run.
Individuality: History, Genetics, and Fortitude
For most people, with so many skills to develop across the three disciplines, there
will always be strengths and weaknesses. Athletic history, personality, and work ethic—
individuality—are unique to each individual and determine the path to optimal race
performance. Science is limited by its inability to determine the impact of individuality
on the effectiveness of different types of training. Individuality creates room for a form of
art—the abstract nature of deciding what is best for an athlete’s unique physiology and
psychology.
18
Athletic history refers to the training an athlete has accumulated to present day.
An individual who grew up swimming will have a solid foundation in swim technique,
whereas an athlete who started swimming during adulthood will be heavily limited by
technique. Former swimmers will not need to spend nearly as much time training their
swim and can spend those resources on developing cycling and running abilities. A
similar philosophy applies to other sports; athletes who grew up running can sustain
greater volumes of running with relatively low risks of injury. Newer runners need to be
more cautious when increasing run mileage.
Each athlete also has different genetics and fortitude. Genetics, similar to the
concept of talent, in part determines the potential of an athlete and how quickly and
effectively they can achieve their potential. Fortitude refers to the athlete’s work ethic, or
how much effort they are willing to expend trying to improve. There are countless
physical and psychological factors that impact both grit and genetics. Many factors are
also impossible to quantify, such as pain tolerance, motivation, or the ability to deal with
lack of motivation or stress. The best approach to designing triathlon training identifies
these abstract elements of life and integrates them, whereas a training program that
constantly conflicts with life will result in missed workouts and additional stress.
19
Strength Training Physiology and Potential Benefits
Physiological Demands of Triathlon Performance
Elite triathlon performance is marked by high aerobic capacity (VO2max), lactate
threshold, and movement economy (Sleivert & Rowlands, 1996). VO2max is an
individual’s maximum capacity for oxygen consumption during exercise. Lactate
threshold refers to an exercise intensity at which an athlete transitions to a greater
reliance on anaerobic metabolism as opposed to aerobic metabolism; exercising at an
intensity greater than lactate threshold exponentially reduces time to exhaustion.
Movement economy describes how much power or speed can be produced with a defined
amount of oxygen; a more economical athlete can produce greater power with a lower
demand for oxygen (Bassett & Howley, 2000).
Basic Muscle Physiology
Skeletal muscle is under voluntary control and allows for locomotion. For
example, contracting the quadriceps extends the leg at the knee, and contracting the
biceps flexes the arm at the elbow. Skeletal muscle fibers are typically categorized as
Type I, Type IIa, or Type IIx fibers. Type I fibers are also known as slow-twitch fibers,
and Type II fibers are also known as fast-twitch fibers. The following table describes
characteristics of each type of fiber relative to each other.
20
Type I (slow) Type IIa (fast-oxidative) Type IIx (fast-glycolytic)
• High fatigue resistance
• Highly aerobic energy
production
• Low cross-sectional
area
• Low force production
• Low rate of force
production
• Medium fatigue
resistance
• Moderately aerobic
energy production
• Moderate cross-
sectional area
• Moderate force
production
• High rate of force
production
• Low fatigue
resistance
• Anaerobic energy
production
• High cross-sectional
area
• High force production
• High rate of force
production
(Gollnick, Armstrong, Saubert, Piehl, & Saltin, 1972)
Triathlon is an aerobically-demanding endurance sport and requires fatigue
resistance, so faster race times are correlated with greater proportions of Type I fibers
(Inbar, Kaiser, & Tesch, 1981). However, fiber type is not the most important
determinant of success in endurance events, as athletes with a variety of proportions of
fiber types have seen success. Other factors, such as aerobic capacity, lactate threshold,
and movement economy, play large roles in determining one’s performance as well
(Coyle, 1995). There is also debate over whether or not training can induce a
physiologically-meaningful conversion of Type II fibers to Type I fibers within a muscle
(Wilson et al., 2012). Regardless of fiber composition, performance can be significantly
improved via adaptation of existing fibers. Endurance training improves capillary density,
mitochondrial function, force production, and cross-sectional area of Type I fibers.
Endurance training can also cause a shift in Type II fibers from the more anaerobic Type
IIx to the more aerobic Type IIa (Hawley & Stepto, 2001).
The effect of strength training on skeletal muscle depends on parameters such as
load (weight), number of repetitions, number of sets, and speed of contraction.
Adaptations to strength training include increased muscle size (hypertrophy), strength,
21
endurance, and/or rate of force production and can be summarized by the strength-
endurance continuum: fewer repetitions (1-6) heavy loads improve strength, many
repetitions (15+) of light loads improve endurance, and rate of force production is
improved by lifting with high contraction velocities (Schoenfeld, Peterson, Ogborn,
Contreras, & Sonmez, 2015).
Popular weight lifting sources commonly state moderate repetitions (8-12) of
moderately-heavy loads lead to greatest hypertrophy, while performing many repetitions
with lighter loads do not yield hypertrophy. However, similar degrees of hypertrophy
have been observed across the strength-endurance continuum irrespective of load
provided the total volume of the workouts are the same across conditions i.e. 3 repetitions
of 100 pounds vs. 15 repetitions of 20 pounds (Haun Cody T. et al., 2017). These
observations lead to theories suggesting hypertrophy is governed significantly by total
metabolic stress and muscle damage—lifting to closer to failure, therefore inducing high
metabolic stress and muscle damage, may be more important than the weights used in
yielding hypertrophy (Schoenfeld, 2010). However, reaching such metabolic stress and
muscle damage with light loads takes much more time, which makes using heavier loads
more efficient in achieving hypertrophy. A practical subjective measure of metabolic
stress and muscle damage is how fatigued the athlete feels after the workout—an
extremely demanding bout of weight lifting likely creates more hypertrophic stimulus,
whereas a relatively unchallenging workout does not.
22
Strength Training and Endurance Performance in Trained Individuals
In the case of endurance sports, significant hypertrophy is not desirable due to the
accompanied increase in body mass and therefore oxygen consumption. Greater body
mass, lean or fat, is detrimental to endurance performance due to associated decreases in
relative VO2max (Maciejczyk, Wiecek, Szymura, Szygula, & Brown, 2015). Minimizing
hypertrophy means minimizing metabolic stress and muscle damage while still
generating enough stimuli to yield strength adaptations.
A large majority of scientific literature supports the use of heavy and explosive
strength training to improve endurance sports performance. The performance gains
resulting from strength training are linked to improvements primarily in exercise
economy, not energy metabolism (Beattie, Kenny, Lyons, & Carson, 2014; Rønnestad &
Mujika, 2014). To improve exercise economy, it is crucial for the athlete to lift near-
maximal loads to create improvements in endurance performance; high-repetition low-
load weight lifting is much less effective in trained individuals (Ebben et al., 2004).
Strength training does not improve VO2max nor does it improve lactate threshold
(LT) as a percent of VO2max (O2 consumption at LT divided by VO2max). However,
exercise economy, maximal velocity (Vmax, maximal velocity at the end of an incremental
treadmill test) and peak power output (Wmax, maximal power output at the end of an
incremental cycle test) do improve (Taipale et al., 2010). Because exercise economy
increases (O2 consumption at a given velocity or power output decreases), velocity and
power output at lactate threshold also increase. Higher Vmax and Wmax values are
indicative of improved anaerobic capacity and neuromuscular characteristics and
23
contribute to improved endurance performance (Baumann, Rupp, Ingalls, & Doyle,
2012).
Exercise economy is improved through various mechanisms. First, heavy strength
training increases the force production of type I muscle fibers. An exercise at an intensity
previously requiring activation of type II muscle fibers, due to force production demands,
can subsequently be performed with a greater proportion of type I fiber activation,
because the maximal-strength-trained type I fibers have been trained to produce more
force (Rønnestad, Hansen, & Raastad, 2011).
Second, heavy strength training yields neuromuscular adaptations improving
coordination and motor recruitment patterns. Through this process, the nervous system
becomes more efficient by minimizing recruitment of fibers that do not contribute
directly toward force production. This is hypothesized to improve endurance performance
by reducing the number of muscle fibers required to achieve a given force output. Less
active muscle fiber recruitment leads to a reduction in overall muscle fatigue in a given
time. This has been demonstrated in a study of cyclists, where MRI and EMG analysis
showed that increased maximum strength reduced the amount of activated muscle mass
to produce the same absolute submaximal power (Bieuzen, Lepers, Vercruyssen,
Hausswirth, & Brisswalter, 2007).
Heavy strength training and explosive strength training increase stiffness of the
muscle-tendon system. Increased muscle and tendon stiffness increases elastic energy
return during the stretch-shortening cycle of muscle while running. Runners with stiffer
muscles and tendons, and therefore greater elastic energy return, have better running
economy (Trehearn & Buresh, 2009). This mechanism does not provide benefits during
24
cycling, however, as the stretch-shortening cycle relies on the eccentric loading of
muscle. Cycling is dominated by concentric contractions (Rønnestad & Mujika, 2014).
Similar mechanisms seem to benefit swimmers as well. Improved maximal force,
rate of force production, and neuromuscular efficiency have been shown to improve
distance swimming performance. Core strength plays a significant role in generating
forward-propulsion during swimming too (Crowley, Harrison, & Lyons, 2017).
Injury Rehabilitation and Prevention
Strength training plays important roles in preventing and rehabilitating training-
related overuse injuries. Athletes who have recurring tendon injuries will benefit from
regular strength training, as resistance exercise increases the number and packing density
of collagen fibrils in tendons. Resistance exercise also facilitates the restructuring of a
healing tendon by encouraging the fibers to align themselves parallel to the direction of
force (Brumitt & Cuddeford, 2015). Rehabilitation of some specific tendon injuries is
most effective with loaded eccentric movements. Though the mechanisms behind
eccentric rehabilitation are relatively unknown, collagen synthesis increases significantly
following eccentric training (Langberg et al., 2007). Examples of eccentric exercises
include calf raises applying both legs in a quick (1s) concentric phase and one leg in a
slow controlled (4s) eccentric phase; and squats using the same technique of two-leg
concentric, one-leg eccentric technique, similar to the calf raise.
25
General Health: Aging, Sarcopenia, and Bone Health
The strength training debate changes when considering older athletes and
individuals with low bone density, particularly since general health is more important
than endurance sport performance. Sarcopenia, the age-related decline in muscle mass,
will eventually lead to strength limitations, and strength training helps maintain both
muscle mass and bone density (American College of Sports Medicine et al., 2009). Truly-
limited muscular strength does impair endurance sport performance, and it eventually
affects the individual’s ability to carry out everyday tasks. Maintaining muscle mass with
strength training reduces the risk of osteoporosis and the signs and symptoms of multiple
chronic diseases. In general, strength training combats weakness and frailty and their
debilitating consequences (Seguin & Nelson, 2003). An athlete in their forties or fifties
might not be experiencing strength declines significant enough to cause symptoms but
starting a strength training routine at their present age may set a foundation for improved
health during older age.
Bone mineral density (BMD) is a concern for swimmers and cyclists. Athletes
who spend a large amount of time swimming or cycling are effectively spending time
with relatively unloaded bones. BMD decline is accelerated in these individuals and
creates an increased risk for osteoporosis (Abrahin et al., 2016). Because strength
training has positive effects on BMD, strength training should be a consideration in any
swimmer or cyclist’s training program. Runners have higher site-specific BMD (lower
limb bones) due to impact forces and the weight-bearing nature of the sport (Duncan et
al., 2002), provided they have adequate nutrition. However, distance runners are still at
risk for low BMD in the spine (Bilanin, Blanchard, & Russek-Cohen, 1989; Hind,
26
Truscott, & Evans, 2006). More research is needed to determine if distance running is a
cause of low spinal BMD, as there are potentially-confounding implications of low body
mass, inadequate nutrition, and lifestyle that are common among distance runners,
especially females (Burrows, Nevill, Bird, & Simpson, 2003; Hind et al., 2006). To
summarize, strength training plays an important role in maintaining general health and
wellness and in contributing to BMD.
Art: A Balancing Act
Empirical evidence clearly suggests that heavy strength training improves
endurance performance via increased movement economy. The question can be asked
then, shouldn’t all triathletes lift heavy weights? The answer lies within the strengths,
weaknesses, and non-sporting life of the athlete. Most triathletes are already time-
constrained to the point they cannot accumulate optimal volume in each of the three
sports. Trying to fit in two strength training sessions or replacing swim/bike/run workouts
with strength training could possibly reduce performance, because the athlete is not
training enough in the three sports that make up triathlon. Heavy strength training also
comes with the cost and time requirement of going to the gym, both of which contribute
to overall stress and spend part of one’s stress budget.
Furthermore, heavy strength training is hard. The athlete must consider if the
benefit of strength training outweighs the negative impacts of its associated fatigue on
swim/bike/run sessions. Fatigue from strength training, even if no delayed-onset muscle
soreness is present, reduces endurance exercise performance and adaptations for up to 72
hours due to reduced neuromuscular drive. Furthermore, if the athlete has some level of
27
chronic fatigue due to strength training, even if at levels so low it becomes hard to
distinguish from swim/bike/run-induced fatigue, endurance development is likely
hindered (Doma, Deakin, & Bentley, 2017). A study with rowers showed athletes who
completed a modest amount of strength training (never lifting to failure) performed better
than athletes who performed a greater amount of strength training (lifting to failure)
(Izquierdo-Gabarren et al., 2010).
This makes strength training program design, or a lack thereof, a subjective and
abstract decision-making process. If high force production is a major limiter for an
athlete, then replacing endurance workouts with strength training could result in
improved performance. If an athlete has enough muscle mass and force production for
triathlon purposes, then adding strength training may be excessively fatiguing and
negatively impact more important endurance-focused workouts. Therefore, the debate
exists in regard to how much strength training constitutes enough in the sport of triathlon.
Elite coach Jesse Kropelnicki applies the concept of lean body mass index (BMI),
which is the BMI of an individual calculated using calculated body weight based on ideal
body composition for racing. Lean BMI is a representation of how much muscle an
individual has. A high lean BMI value means the athlete likely does not have a strength
limitation and vice versa for low lean BMI. His anecdotal experience suggests female
athletes perform best at lean BMI of 20, and males at 21. To find lean BMI, the athlete
first undergoes a body composition test to estimate body fat percentage (BF%). BF% is
used to calculate existing fat mass and subsequently how much fat mass must be lost to
reach ideal body composition. The value for target fat mass loss is subtracted from total
body weight to yield lean body weight, and lean body weight is used to calculate lean
28
BMI with the same equation that would be used for normal BMI (Jesse Kropelnicki,
2011).
In the context of single-sport athletes who might not carry as much fatigue due to
lower overall training volume compared to triathletes, adding strength training might
often be more feasible and appropriate. It may also be easier for single-sport athletes to
reach adequate volumes of training in their respective sports, whereas time-constrained
triathletes must juggle training for three sports. One must also consider if the athlete
enjoys strength training. If the athlete has no desire to lift weights and is not significantly
limited by their strength, then they are probably better off spending the time on
swim/bike/run. If the athlete perceives benefit and enjoys strength training, then it may be
worth considering.
If Strength Training Is Desired: How-To
Many training resources portray strength training as an all-or-nothing approach,
but this is unhelpful for athletes who have only twenty minutes a week for strength
training. The top result of a “triathlon strength training” Google search reveals Mark
Allen’s (six time Ironman World Champion) recommended weight lifting program of
twelve exercises performed twice a week throughout the entire year (Allen, n.d.). Joe
Friel’s popular book, The Triathletes Training Bible, outlines a periodized weight lifting
program consisting of two to three sessions in the gym per week (Friel, 2016) It is
presented in a very structured format without any suggestions for alternatives. Both
Allen’s and Friel’s programs consist of periodized year-long cycles with significant
progressions every several weeks.
29
Athletes with little time to lift weights may benefit from rethinking the traditional
strength training periodization reported in both popular training resources and scientific
literature. Good training involves dynamic year-to-year consistency in addition to within-
year consistency. There are peaks and nadirs with adjustments being made along the way
due to unforeseen life occurrences. However, the general trajectory is steady progress.
Athletes should think about strength training with a similar mindset and utilize a
conservative long-term approach based on consistency, gradual progression, and
flexibility.
Traditional strength periodization principles that are often found in endurance-
focused strength training books are similar to the following:
1. Adaptation Phase: low weights and a high number of repetitions (15-20) are
used for four to six weeks to build general strength in preparation for heavier
loads.
2. Transition Phase: the weight is increased significantly over 2-4 weeks while
the number of repetitions is decreased (6-12) to transition from light loads
used in the adaptation phase to the heavy loads of the maximum strength
phase.
3. Maximum Strength Phase: the weight approaches near 1-repetition
maximums and repetitions are low (3-5). A large amount of rest (3+ minutes)
provides full recovery in order to lift heavy loads with quality. The maximum
strength phase lasts until competition season demands increased emphasis on
freshness and race-day performance.
30
4. Power or Maintenance: after the maximum strength phase, some sources will
instruct athletes to move to a power phase in which loads are decreased and
emphasis is placed on the speed of contraction to maximize power. Plyometric
exercises are the classic example of power training. Other sources suggest
moving straight from maximum strength to in-season maintenance in which
the athlete will still lift heavy loads but in significantly reduced volumes (i.e.
fewer sets) to maintain strength while minimizing fatigue.
These traditional principles fall under a linear periodization format, which makes logical
sense on paper. Consider, however, the following questions: what if an athlete misses two
weeks of strength training due to other life commitments? Does this periodization
structure need to be followed every year in this order? What other options exist?
First, general foundational strength is necessary before performing any sort of
heavily-loaded or advanced movement. Not only is this important for injury prevention,
but building stability first actually increases subsequent lifting performance (Hammami,
Granacher, Makhlouf, Behm, & Chaouachi, 2016). In other words, an adaptation phase
should be a part of any strength training program if the athlete has not been regularly
weightlifting prior to beginning the program.
After foundational strength has developed, athletes have much more flexibility
than generally described in popular triathlon training books (explained later). The goals
of strength training remain similar—increase maximum force production and/or rate of
force production while minimizing muscle hypertrophy. This means the athlete should
still aim to perform few repetitions at high weight in compound movements or power-
focused explosive exercises. However, the athlete does not have to be fixed in a rigid
31
linear periodization plan; the plan can be constantly evolving to fit the athlete’s life and
schedule.
This type of “evolving” strength training program is essentially undulating
periodization. Instead of having training phases with distinct repetitions and weights, the
athlete constantly switches between adaptation-, transition-, maximum-strength-, and
power-type exercises depending on what is most appropriate at that time. For example:
• If the athlete is emerging from a period of time with minimal weightlifting and
lacks foundational strength and stability, adaptation is necessary.
• If the athlete has been in a maximum strength phase but encounters two weeks
with no lifting, they could return to a couple of weeks of transition-type
repetitions and weights to ease back into near-maximum weights.
• If the athlete has two busy upcoming weeks at work and can lift only once per
week, maximum strength and power can be maintained by doing a couple of
specific exercises for each of those two workouts After those two weeks, the
athlete can resume lifting two or three times per week.
• If the athlete has a few races spaced one month apart and wants to minimize
weightlifting-induced fatigue while maintaining strength and power, the weeks
can be structured in the following cycle: race, maximum strength, power,
maintenance.
A flexible or undulating weightlifting program is not inferior to a linear program. An
undulating program may actually yield better results due to the ability to allocate
different types of sessions where they are most appropriate (Harries, Lubans, & Callister,
2016). This flexibility allows the athlete to optimize adaptation and to minimize fatigue
32
when needed, and there are few to no downsides of alternating between types of
weightlifting (i.e. switching between heavy lifting and explosive training within a season
(Hartmann et al., 2015).
If strength training sessions are skipped for several weeks for various reasons, it
may be risky to resume strength training with the same weight load, as some stability or
technical skill may have been lost. If this is the case, the athlete can resume strength
training with lighter loads (similar to adaptation weight) to re-establish stability before
progressing back to heavier loads to minimize injury risk. Missing a few weeks of
strength training is a not significant hindrance if long-term consistency is maintained. An
inactivity period of up to three weeks does not significantly decrease muscle strength or
impair subsequent adaptation to resumed strength training (Gentil et al., 2015;
Ogasawara, Yasuda, Sakamaki, Ozaki, & Abe, 2011). Missing more than three weeks
will result in a detraining effect. However, previous strength training facilitates retraining
following a period of retraining, and any strength losses can be regained much more
quickly (Lee, Hong, & Kim, 2016). It is hypothesized the rapid retraining is a result of
“muscle memory” is a result of the fact that the number of nuclei in muscle cells
(myonuclei) increase with strength training. During disuse and atrophy, these myonuclei
are not lost and may contribute to subsequent adaptation (Bruusgaard, Johansen, Egner,
Rana, & Gundersen, 2010). Thus, the benefits of strength training can be improved on or
maintained year to year even if there are periodic breaks from strength training. There is,
of course, a line that must be drawn for how much strength training is enough to yield
desired results, as there is a minimum threshold of training volume and intensity that
must be crossed to cause adaptation (Schoenfeld, 2013).
33
Summary
There is no single correct or perfect training program. It is up to the athlete or
coach to analyze the pros and cons of adding strength training and, if strength training is
performed, to create a strength training program that fits the athlete’s life. The following
sections provide a summary of approaching strength training for triathletes, with the
caveat that there are clearly endless modifications for any suggestions. It is ultimately a
summary of my personal views on strength training for triathletes that integrates science,
art, and anecdote to try to answer the following question: what should I do right now to
maximize performance on race day?
Questions to ask:
• Does the athlete want to strength train?
• Is the athlete doing adequate swim/bike/run volume?
• Is the athlete strength-limited or experiencing age-related bone or muscle
degeneration?
• Does the athlete have enough time to add in strength training?
See the flow chart for a visual reference on the decision-making process.
34
35
Guidelines for Levels of Focus
High focus
• Dedicate an adequate portion of available stress and energy to strength training in
order to perform high quality strength workouts
o Reduce swim/bike/run volume and intensity to avoid being fatigued going
into strength workouts
o Maintain high consistency (2-3 times per week) by prioritizing strength
workouts over swim/bike/run workouts when overall training time needs
to be reduced
• Build stability before hypertrophy, maximum strength, and power
o Adaptation (many repetitions, low weights) before maximum strength
(few repetitions, heavy loads)
o Resume with adaptation-type lifting following any breaks
▪ Develop good technique before high effort and heavy weights
• Aim for muscle hypertrophy until lean BMI increases to ~21
o During strength workouts, lift until near-failure without compromising
form
o Focus on compound movements that apply to swim/bike/run
▪ Squat, deadlift, lunge, bench press, pull up/lat pull down, seated
row
• Eat a large amount of protein (2.0 grams per kilogram of bodyweight per day)
while maintaining a mild caloric surplus (300-500 calories per day) to maximize
muscle hypertrophy (Stark, Lukaszuk, Prawitz, & Salacinski, 2012)
36
• Move to maximal strength and power after target lean BMI is reached
Moderate focus
• Strength training has a similar priority to swim/bike/run workouts
o During times of high stress or low time availability, reduce both strength
and swim/bike/run workouts
• Build stability before hypertrophy, maximum strength, and power
o Adaptation (many repetitions, low weights) before maximum strength
(few repetitions, heavy loads)
o Resume with adaptation-type lifting following any breaks
▪ Develop good technique before high effort and heavy weights
• Lift to maximize strength while keeping hypertrophy minimal
o Lift at a perceived effort of moderate challenge/fatigue during workouts
o Lift heavy weights close to 1-repetition-maximums with plenty of rest (i.e.
5x3 squats with 3-5 minutes rest)
• Balance swim/bike/run-induced and strength-training-induced fatigue
• Eat a moderate amount of protein
Low focus
• Train mindfully and be ready to make adjustments
o The subsequent days of training are just as important as the present day
37
▪ If significant heavy lifting today feels like it will compromise
future training with excess fatigue, reduce the volume and intensity
of the workout
▪ Skip strength workouts during times of high stress or low time
availability
• Build stability before hypertrophy, maximum strength, and power
o Adaptation (many repetitions, low weights) before maximum strength
(few repetitions, heavy loads)
o Resume with adaptation-type lifting following any breaks
▪ Develop good technique before high effort and heavy weights
• Minimize hypertrophy and fatigue
o Stop sets significantly before the point of failure
o Lift to a perceived effort of low to moderate challenge
o Low overall lifting volume and physical stress
▪ Finish feeling strong and invigorated, not sore and tired
o Lift moderately heavy weights close to 3-repetition-maximums with
plenty of rest (i.e. 5x3 squats with 3-5 minutes rest)
• Eat a moderate amount of protein
38
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