High-Intensity Interval Training Interventions in Children and Adolescents: A Systematic Review
Sports Med
High-Intensity Interval Training Interventions in Children and Adolescents: A Systematic Review
William T. B. Eddolls 0 1
Charles O. N. Winn 0 1
Melitta A. McNarry 0 1
Kelly A. Mackintosh 0 1
Key Points 0 1
0 School of Sport Health and Exercise Science, University of Western Australia , Perth, WA , Australia
1 Applied Sports Science Technology and Medicine Research Centre (A-STEM), College of Engineering, Swansea University , A101 Engineering East, Bay Campus, Fabian Way, Swansea SA1 8EN , UK
Background Whilst there is increasing interest in the efficacy of high-intensity interval training in children and adolescents as a time-effective method of eliciting health benefits, there remains little consensus within the literature regarding the most effective means for delivering a highintensity interval training intervention. Given the global health issues surrounding childhood obesity and associated health implications, the identification of effective intervention strategies is imperative. Objectives The aim of this review was to examine highintensity interval training as a means of influencing key health parameters and to elucidate the most effective highintensity interval training protocol. Methods Studies were included if they: (1) studied healthy children and/or adolescents (aged 5-18 years); (2) prescribed an intervention that was deemed high intensity; and (3) reported health-related outcome measures. Results A total of 2092 studies were initially retrieved from four databases. Studies that were deemed to meet the criteria were downloaded in their entirety and independently assessed for relevance by two authors using the predetermined criteria. From this, 13 studies were deemed suitable. This review found that high-intensity interval training in children and adolescents is a time-effective method of improving cardiovascular disease biomarkers, but evidence regarding other health-related measures is more equivocal. Running-based sessions, at an intensity of [90% heart rate maximum/100-130% maximal aerobic velocity, two to three times a week and with a minimum intervention duration of 7 weeks, elicit the greatest improvements in participant health. Conclusion While high-intensity interval training improves cardiovascular disease biomarkers, and the evidence supports the effectiveness of running-based sessions, as outlined above, further recommendations as to optimal exercise duration and rest intervals remain ambiguous owing to the paucity of literature and the methodological limitations of studies presently available.
-
While this review enables the establishment of
suggested guidelines for high-intensity interval
training protocols, recommendations for some
protocol details remain unclear.
1 Introduction
Worldwide, the prevalence of childhood and adolescent
obesity has reached unparalleled levels [
1, 2
]. Specifically,
in the UK, approximately 28% of children are classified as
overweight or obese [
2, 3
], representing a significant
burden on health services. Indeed, current estimates suggest
that obesity and its deleterious health consequences, such
as type 2 diabetes mellitus [
4
] and coronary heart disease
[
5
], cost the National Health Service £5.1 billion per year
[
6
]. Whilst some reports suggest a plateau in paediatric
obesity over the last decade [
7
], others suggest that UK
obesity levels have increased between 1980 and 2014 by 48
and 39% in boys and girls, respectively [
2
]. Of concern,
paediatric obesity has been associated with an increased
prevalence of cardiometabolic risk factors [
8
], which have
been shown to track into later life [
9
] and increase the risk
of premature mortality [
9, 10
]. Although the causes of
obesity and cardiometabolic risk are multifaceted, low
physical activity levels, as well as high engagement in
sedentary pursuits, have been identified as key contributory
factors [
9, 11–13
]. Specifically, according to the latest
statistics, in England, only 21% of boys and 16% of girls
meet UK physical activity guidelines of at least 60 min of
moderate-to-vigorous physical activity every day [
3
], with
physical activity levels further declining with age [
14–16
].
Effective interventions targeted at increasing youth
physical activity levels are therefore imperative.
While traditional interventions designed to increase
physical activity and improve health have principally used
moderate-intensity continuous exercise [
17–19
], the
relevance of such programmes to the sporadic high-intensity
nature of children’s habitual play patterns has been
questioned [
20
]. Consequently, high-intensity interval-based
programmes have recently been investigated as a
potentially potent and time-efficient form of physical activity
and health promotion [
21
]. Indeed, whilst exercise, a
subcomponent of physical activity, is structured and conducted
for the health-associated benefits, it could provide a
necessary mediatory step to provoke po (...truncated)