The Evolution of World-Class Endurance Training: The Scientist’s View on Current and Future Trends

Abstract

Background:
Elite sport is continuously evolving. World records keep falling and athletes from a longer list of countries are involved.

Purpose:
This commentary was designed to provide insights into present and future trends associated with world-class endurance training based on the perspectives, experience, and knowledge of an expert panel of 25 applied sport scientists.

Results:
The key drivers of development observed in the past 10-15 years were related to (1) more accessible scientific knowledge for coaches and athletes combined with (2) better integration of practical and scientific exchange across multidisciplinary perspectives within professionalized elite athlete support structures, as well as (3) utilization of new technological advances. Based on these perspectives, we discerned and exemplified the main trends in the practice of endurance sports into the following categories: better understanding of sport-specific demands; improved competition execution; larger, more specific, and more precise training loads; improved training quality; and a more professional and healthier lifestyle. The main areas expected to drive future improvements were associated with more extensive use of advanced technology for monitoring and prescribing training and recovery, more precise use of environmental and nutritional interventions, better understanding of athlete-equipment interactions, and greater emphasis on preventing injuries and illnesses.

Conclusions:
These expert insights can serve as a platform and inspiration to develop new hypotheses and ideas, encourage future collaboration between researchers and sport practitioners, and, perhaps most important, stimulate curiosity and further collaborative studies about the training, physiology, and performance of endurance athletes.

Full text

The Evolution of World-Class Endurance Training:
The Scientist’s View on Current and Future Trends
Øyvind Sandbakk,
1
David B. Pyne,
2
Kerry McGawley,
3
Carl Foster,
4
Rune Kjøsen Talsnes,
1
Guro Strøm Solli,
5
Grégoire P. Millet,
6
Stephen Seiler,
7
Paul B. Laursen,
8,9
Thomas Haugen,
10
Espen Tønnessen,
10
Randy Wilber,
11
Teun van Erp,
12
Trent Stellingwerff,
13
Hans-Christer Holmberg,
14,15
and Silvana Bucher Sandbakk
16
1
Center for Elite Sports Research, Department of Neuromedicine and Movement Science, Norwegian University of Science and Technology, Trondheim, Norway;
2
Research Institute for Sport and Exercise, University of Canberra, Canberra, ACT, Australia;
3
Swedish Winter Sports Research Center, Department of Health Sciences,
Mid Sweden University, Östersund, Sweden;
4
Department of Exercise and Sport Science, University of Wisconsin–La Crosse, La Crosse, WI, USA;
5
Department of Sports Science and Physical Education, Nord University, Bodø, Norway;
6
Institute of Sport Sciences, University of Lausanne, Lausanne, Switzerland;
7
Department of Sport Science and Physical Education, University of Agder, Kristiansand, Norway;
8
Sports Performance and Athlete Development Environments
(SPADE), University of Agder, Kristiansand, Norway;
9
Sports Performance Research Institute New Zealand (SPRINZ), AUT University, Auckland, New Zealand;
10
School of Health Sciences, Kristiania University College, Oslo, Norway;
11
United States Olympic Committee, Colorado Springs, CO, USA;
12
Division of Movement Science and Exercise Therapy (MSET), Department of Exercise, Sport and Lifestyle Medicine, Faculty of Medicine and Health Sciences,
Stellenbosch University, Tygerberg, South Africa;
13
Canadian Sport Institute—Pacific, Victoria, BC, Canada;
14
Department of Health Sciences,
Luleå University of Technology, Luleå, Sweden;
15
School of Kinesiology, University of British Columbia, Vancouver, BC, Canada;
16
Department of Teacher Education, Norwegian University of Science and Technology, Trondheim, Norway
Background:Elite sport is continuously evolving. World records keep falling and athletes from a longer list of countries are
involved. Purpose:This commentary was designed to provide insights into present and future trends associated with world-class
endurance training based on the perspectives, experience, and knowledge of an expert panel of 25 applied sport scientists.
Results:The key drivers of development observed in the past 10–15 years were related to (1) more accessible scientific
knowledge for coaches and athletes combined with (2) better integration of practical and scientific exchange across multi-
disciplinary perspectives within professionalized elite athlete support structures, as well as (3) utilization of new technological
advances. Based on these perspectives, we discerned and exemplified the main trends in the practice of endurance sports into the
following categories: better understanding of sport-specific demands; improved competition execution; larger, more specific, and
more precise training loads; improved training quality; and a more professional and healthier lifestyle. The main areas expected to
drive future improvements were associated with more extensive use of advanced technology for monitoring and prescribing
training and recovery, more precise use of environmental and nutritional interventions, better understanding of athlete–
equipment interactions, and greater emphasis on preventing injuries and illnesses. Conclusions:These expert insights can serve
as a platform and inspiration to develop new hypotheses and ideas, encourage future collaboration between researchers and sport
practitioners, and, perhaps most important, stimulate curiosity and further collaborative studies about the training, physiology,
and performance of endurance athletes.
Keywords:athlete health, endurance performance, sport technology, training intensity, training load, training quality
Elite sport is continuously evolving, as illustrated by world
records being broken and the involvement of a greater diversity of
countries and athletes, driving improvements in athletic perfor-
mance. Explanations for this continued performance evolution are
multifaceted, and likely include the optimization of athlete training
and competitive periodization, as well as recent advancements in
technologies, equipment, and scientific knowledge, all accessible
to larger audiences. However, research on elite athletes is often
constrained by underlying challenges, such as interruptions to
coaching and training programs, as well as limitations in the type,
quality, or applicability of research studies that can be executed
with elite performers. To gain complementary insight into current
and future trends associated with world-class endurance training,
this commentary is based on the perspectives, experience, and
knowledge of an expert panel of applied sports scientists.
Methods
To capture key insights about the evolution of endurance training
and performance, we solicited and aggregated expert judgments
through a structured elicitation protocol. In the first step, 2 ques-
tions were posed by the first and last author to an expert panel of
25 acknowledged sport scientists (5 women and 20 men) with
Pyne https://orcid.org/0000-0003-1555-5079
McGawley https://orcid.org/0000-0002-1273-6061
Talsnes https://orcid.org/0000-0002-4076-2451
Solli https://orcid.org/0000-0002-7354-8910
Millet https://orcid.org/0000-0001-8081-4423
Seiler https://orcid.org/0000-0001-8024-5232
Laursen https://orcid.org/0000-0003-1532-2697
Haugen https://orcid.org/0000-0001-5929-0389
Tønnessen https://orcid.org/0000-0002-7781-4913
van Erp https://orcid.org/0000-0002-2146-9479
Stellingwerff https://orcid.org/0000-0002-4704-8250
Holmberg https://orcid.org/0000-0002-3814-6246
Bucher Sandbakk https://orcid.org/0000-0001-8412-9538
Sandbakk (oyvind.sandbakk@ntnu.no) is corresponding author, https://orcid.org/
0000-0002-9014-5152
1
International Journal of Sports Physiology and Performance, (Ahead of Print)
https://doi.org/10.1123/ijspp.2023-0131
© 2023 Human Kinetics, Inc. INVITED COMMENTARY
First Published Online: June 27, 2023
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experiences of working closely with world-leading endurance
athletes and coaches over the last decade(s). Collectively, this
multinational panel had multidisciplinary (ie, exercise physiology,
biomechanics, sports analytics, nutrition, and sports medicine)
experience of working with male and female athletes from 15
different nations and representing all Olympic endurance sports.
The 2 questions were: (1) What are the most important trends
related directly or indirectly to the training and improved perfor-
mance of the world’s best endurance athletes during the past
10–15 years? and (2) Which advances will contribute to further
improving endurance performance during the next 10–15 years?
To allow diversity of opinion, all scientists were asked to prioritize
3 key points for each question individually, and to explain and
exemplify their choices. Consent was given on the basis that replies
could be used for the purpose of this commentary.
In the next steps, all responses were aggregated into initial
thematic categories by the first and last author. Iterative refinement
was undertaken by facilitated negotiation and discussion over
email among all authors, until final consensus on main categories,
as well as representative examples and explanations was reached.
Recent and Contemporary Trends
in Endurance Training
To address recent and contemporary trends, the answers to the first
question were categorized into 2 dimensions: the underlying
mechanisms driving the development (the why) and the effects
of these factors on sport practices (the what).
A main driver of development in endurance training methods
was more relevant scientific knowledge accessible to coaches and
athletes, combined with better integration and exchange of practi-
cal and scientific knowledge. In this context, easier access to
scientific and experience-based knowledge through open-access
journals, media (eg, popular science articles, podcasts, Twitter,
Instagram, YouTube, etc), and various other communication chan-
nels (eg, conferences/summits, webinars, workshops, personal
conversations, etc) has facilitated faster and wider learning and
possibly more effective implementation into sport practice. Two
potential challenges associated with effective utilization of publicly
available information are (1) the ability to filter useful versus less
useful content and (2) translation of this specific information into a
holistic training process. This translation process will require close
collaboration between athletes, coaches, and various domain
experts.
Another main driver was the implementation of technological
advances, with better equipment and more validated tools/wear-
ables for monitoring and analyzing training, performance, and
recovery. The sports science laboratory has moved out to the
roads, tracks, pools, lakes, trails, rivers, and mountains where
endurance athletes train daily. A critical challenge in this context
is to assure that the continuously collected data stream is as reliable
and valid as possible.
Elite athlete health and performance support structures are
now often organized in multidisciplinary centers or teams. This was
regarded as a complementary factor facilitating effective imple-
mentation of the extended knowledge and new technological
solutions into the holistic training, competition, and performance
process. High-performance sports directors (or equivalent) and
coaches are, in general, now more well-educated in coaching
and/or sports science. In addition, they are more open to the
potential benefits of multi- and intradisciplinary collaboration
among athletes, coaches, scientists, and other experts.
Based on these driving factors, we discerned 5 important
trends in the practice of endurance sports that have evolved over
the last 10–15 years.
Better Understanding of Sport-Specific Demands
A more interdisciplinary and integrated understanding of physio-
logical, technical, tactical, nutritional, and mental aspects underly-
ing performance, on the basis of optimal mental and physical
health, has evolved in sports.
1
For example, different exercise
modes can elicit highly distinct metabolic, mechanical, and mus-
cular loading, which can have significant consequences for training
and recovery processes.
2
In this context, the technological possi-
bility to measure performance, training load, and recovery under
ecologically valid conditions, in combination with advanced per-
formance modeling, has extended our understanding beyond the
traditional performance-determining factors.
3
Examples of com-
plementary concepts are the impact of resilience/durability during
long-duration exercise,
4
or the implementation of various models
describing aerobic and anaerobic kinetics during intermittent exer-
cise. A better understanding of nutritional strategies has also played
a significant role both for optimizing performance, and sustainable
tolerance and execution of high daily training loads. This may
include optimal carbohydrate intake (daily, and during training,
and competition)
5
and associated nutritional periodization to meet
the demands of the sport.
6,7
Improved Competition Execution
More accurate technological measures of performance and
advanced performance models have improved pacing strategies,
8
as well as the ability of each athlete (and their coaches) to identify
and focus on his/her own individual strengths and weaknesses.
Examples of this are the extensive use of various wearable devices,
such as power meters, global positioning/navigation satellite sys-
tems, and inertial movement units in many sports.
9,10
With the
combination of machine learning and domain competence, these
developments have provided new insights in many sports, although
the practical and ethical challenges of accumulating and processing
large sets of personal data should also be acknowledged.
Without doubt, improved equipment has been vital for perfor-
mance development in many endurance sports, with the clap skate
in speed skating,
11
carbon fiber use in cycling, rowing, kayak, and
paralympic events, and “super-shoes”in running
12
being primary
examples. Another factor is improved preparation strategies for
competitions held in different environmental conditions such as
altitude and the heat.
13
Furthermore, sport-specific and individual-
ized nutritional intake during competitions (eg, carbohydrate intake
and the use of various ergogenic aids)
5,14-16
was highlighted by
many of the respondents.
Larger, More Specific, and More Precise
Training Loads
Many of the scientists on the expert panel highlighted that world-
leading endurance athletes now perform and tolerate higher train-
ing volumes than previously recorded. However, others had
observed more precise and calculated training models, allowing
a higher volume or density of competition-specific training. In both
cases, the detection of individualized “sweet-spots”with respect to
training volume and intensity, as well as individualized training
intensity distribution, and more detailed monitoring, and analysis
of capacity developments were highlighted as success criteria. One
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of the trends observed by many of the scientists was more of the
intense training being performed in a “controlled zone,”thereby
allowing higher volume and/or frequency of sessions at competi-
tion-relevant speeds.
17
However, the specific changes in training
patterns, as well as the underlying mechanisms, need to be verified
for different endurance sports.
The following aspects were highlighted as the main facilitators
for athletes accumulating higher training volumes or competition-
specific loads: shorter transition/recovery periods between the
competition period and the following macrocycle, higher training
loads both early in the training year and during the competition
period, and more conscious periodization and load-recovery moni-
toring. Other key factors allowing more precise training loads
included improved training facilities (eg, better roller-ski tracks
for cross-country skiers and biathletes, and more indoor tracks in
cycling, athletics and speed skating), and improved equipment. In
addition, more advanced injury prevention measures seem to
provide better continuity of training.
18,19
More women worldwide now have the possibility to train and
compete professionally in endurance sports, with a higher status of
female competitions, more financial support, and better coaching
available to female athletes. In addition, many sporting environments
now possess greater awareness of, and willingness to communicate
about, aspects of female physiology and health (eg, the influence of
the menstrual cycle,
20,21
hormonal contraception,
22
and pregnancy/
postpartum
23-26
), and their potential impact on training and perfor-
mance. With the increase in professional opportunities for female
athletes, and an improved understanding of the specific challenges
facing women in elite sport, larger, more specific, and/or precise
training loads are particularly observed in female athletes.
Finally, several respondents highlighted that more systematic
inclusion of environmental stressors, such as altitude
27
and heat,
13
periodized in the training process has become more common,
particularly when preparing for events held under challenging
climatic conditions.
Improved Training Quality
Factors associated with improved training quality
28
were
highlighted by many of the respondents. This list included both
the quality of the holistic training process, performed in close
cooperation between athletes, coaches, and multidisciplinary sup-
port teams, as well as better planning, execution, and debriefing
routines of single training sessions. One key factor for the latter
dimension was more precise and disciplined intensity control,
facilitated by greater awareness of how the variables of exercise
prescription influence training tolerance and load, as well as better
technologies to monitor these features in various conditions.
Another example was use of better equipment in training, such
as “super shoes”with new age foams that allow for better cush-
ioning and recovery, thereby facilitating more training at high
speeds. Such developments may also contribute to narrowing the
gap between training prescription and execution.
Improved training quality was also associated with more
individualized training in terms of load prescription, microperio-
dization, and daily session programming. For example, implemen-
tation of strength and power training based on individual profiling
in relation to the physiological and technical requirements of each
sport is now much more advanced in sport practice. Such individual
profiling, in combination with systematic monitoring of training
and testing, provides important objective information concerning
how training is executed and the corresponding adaptations. In
addition, the role of the coach and multidisciplinary support staff in
using such information to prepare and debrief the athlete system-
atically, as well as how the support staff work synergistically with
coaches and athletes,
29
were also highlighted as having a positive
influence on training quality and performance.
A More Professional and Healthier Lifestyle
Employing a more holistic approach to athlete development, by
understanding and considering all factors influencing their lives,
has benefited both individual and team-sport athletes.
30
Greater
professionalization of many sports has enabled athletes to pursue a
full-time athletic career, which can create a healthier lifestyle
through enhanced recovery. More knowledge and greater aware-
ness of injury prevention and health management strategies are
argued as important for facilitating the continuity and sustainability
of training, as well as prolonging the careers of elite athletes.
18
For
example, greater knowledge and awareness of the importance of
energy availability, periodized and individualized nutrition, and
sleep have contributed to improved recovery.
31
The same paradigm
applies to the inclusion of systematic monitoring of recovery
parameters such as resting heart rate, heart rate variability, and
sleep metrics as part of the monitoring systems. In addition, greater
focus on the mental health of athletes
32
and coaches
33
was regarded
as imperative.
Future Trends in Endurance Training
The expert panel generally expected the factors underpinning
improved endurance training and performance to continue to
evolve in the upcoming 10–15 years. However, some perennial
aspects of endurance training received particular attention, and a
few new aspects were highlighted as key areas for improvement in
the future.
First, more extensive and reliable use of advanced technology
for evidence-based monitoring of training, recovery, and perfor-
mance is expected. Importantly, these technologies and the insights
they provide must be combined in a holistic, sport-specific, and
integrated fashion with the individual athlete’s own developmental
needs. This approach will likely allow more effective individuali-
zation of training. In this context, artificial intelligence and its
associated opportunities are evolving very quickly and may permit
individualized prescription of training; for example, when com-
bined with innovative, noninvasive technologies assessing muscle
fiber types and other important individual physiological character-
istics. As part of this process, more detailed knowledge about how
to precisely use combinations of training loads, environmental
stressors, and nutritional interventions to optimize physiological
adaptations and performance is expected. Furthermore, a more
advanced understanding of athlete–equipment interactions leading
to greater tolerance of sport-specific training and improved perfor-
mance is also suggested as a future trend.
A greater emphasis on the prevention of health problems
34
will
allow more athletes to train with continuity over longer durations
and this is clearly an area with further possibilities for improve-
ment. A greater focus on female athletes also creates opportunities
for future improvement,
35
especially given the historical lack of
knowledge and support that has likely limited performance devel-
opment and career longevity in this population. Programs designed
to prevent injuries, illnesses, Relative Energy Deficiency in Sport,
and/or eating disorders and other unhealthy behaviors need to be
customized, fine-tuned, and implemented broadly. Aspects relating
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to the preservation of mental health are also expected to receive
more attention over the coming years. Overall, a more comprehen-
sive approach to optimizing and maintaining good athlete health
should permit more athletes to attain their full potential.
Finally, the continuous development and adjustment of sport
science curriculums within universities and federations in many
countries will translate to improved scientific knowledge among
coaches, athletes, and practitioners, facilitating greater transfer of
knowledge within and between multidisciplinary teams.
Practical Applications and Conclusions
From the perspective of an expert panel of 25 applied sport
scientists, this commentary has facilitated the sharing of ideas,
experience, and knowledge between individuals involved in a
variety of endurance sports, research areas, and athletic communi-
ties. These insights are summarized in Table 1and can serve as a
platform and inspiration for developing new hypotheses, encour-
age future collaboration between researchers and sport practi-
tioners, and, perhaps most importantly, stimulate curiosity and
fruitful collaborative studies about the training, physiology, health,
and performance of endurance athletes. It would be highly enlight-
ening to pose these same questions to elite-level athletes, coaches,
and support staff within different sports and nations. Although
most of the content in this commentary should be relevant both for
Olympic and Paralympic endurance sports, the evolution of para-
specific aspects should be further explored in upcoming studies.
Acknowledgments
The first author of this commentary is the editor of the International
Journal of Sports Physiology and Performance, and several of the
authors are associate editors or editorial board members of the journal.
Laursen is cofounder of HIIT Science Inc and Athletica Inc. The
possibility of publication bias was discussed critically and evaluated
among editors, and none of the authors, including those with editorial
roles, had the opportunity to influence the independent review process.
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Table 1 Summary of the Present and Future Trends Associated With World-Class Endurance Training Based
on the Perspectives, Experience, and Knowledge of an Expert Panel of 25 Applied Sport Scientists
Key drivers of development observed
in the past 10–15 y
Main trends in the practice of
endurance sports in the past 10–15 y
Main areas expected to drive future
improvements
•More accessible scientific knowledge for
coaches and athletes
•Better integration of practical and scientific
knowledge exchange across
multidisciplinary perspectives within
professionalized elite athlete support
structures
•Utilization of new technological advances
•Better understanding of sport-specific
demands
•Improved competition execution
•Larger, more specific, and precise training
loads
•Improved training quality
•A more professional and healthier lifestyle
•More extensive use of advanced technology
for monitoring and prescribing training and
recovery
•More precise use of heat and altitude
interventions, and nutritional interventions
•Better understanding of athlete–equipment
interactions
•Greater emphasis on preventing injuries and
illnesses
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