1 London Sport Institute, Middlesex University, Allianz Park, Greenland Way, London, NW4 1RLE, UK
2 School of Sport, Health and Applied Science, St Mary’s University College, Twickenham, UK
3 Ipro Interactive Ltd, Oxfordshire, UK
4 School of Life Sciences, Kingston University, London, UK
5 Nicholas Institute of Sports Medicine and Athletic Trauma, Lenox Hill Hospital, New York, NY, UK
6 Faculty of Health and Life Sciences, Northumbria University, Newcastle-upon-Tyne, UK
7 Water Research Group, School of Biological Sciences, North West University, Potchefstroom, South Africa
2 School of Sport, Health and Applied Science, St Mary’s University College, Twickenham, UK
3 Ipro Interactive Ltd, Oxfordshire, UK
4 School of Life Sciences, Kingston University, London, UK
5 Nicholas Institute of Sports Medicine and Athletic Trauma, Lenox Hill Hospital, New York, NY, UK
6 Faculty of Health and Life Sciences, Northumbria University, Newcastle-upon-Tyne, UK
7 Water Research Group, School of Biological Sciences, North West University, Potchefstroom, South Africa
Journal of the International Society of Sports Nutrition 2015, 12:22
doi:10.1186/s12970-015-0085-8
The electronic version of this article is the complete one and can be found online at: http://www.jissn.com/content/12/1/22
The electronic version of this article is the complete one and can be found online at: http://www.jissn.com/content/12/1/22
| Received: | 10 February 2015 |
| Accepted: | 4 May 2015 |
| Published: | 11 May 2015 |
© 2015 Dimitiou et al.; licensee BioMed Central.
This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly credited. The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated.
This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly credited. The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated.
Abstract
Background
Prolonged exercise, such as marathon running, has been associated with an increase
in respiratory mucosal inflammation. The aim of this pilot study was to examine the
effects of Montmorency cherry juice on markers of stress, immunity and inflammation
following a Marathon.
Methods
Twenty recreational Marathon runners consumed either cherry juice (CJ) or placebo
(PL) before and after a Marathon race. Markers of mucosal immunity secretory immunoglobulin
A (sIgA), immunoglobulin G (IgG), salivary cortisol, inflammation (CRP) and self-reported
incidence and severity of upper respiratory tract symptoms (URTS) were measured before
and following the race.
Results
All variables except secretory IgA and IgG concentrations in saliva showed a significant
time effect (P <0.01). Serum CRP showed a significant interaction and treatment effect (P < 0.01). The CRP increase at 24 and 48 h post-Marathon was lower (P < 0.01) in the CJ group compared to PL group. Mucosal immunity and salivary cortisol
showed no interaction effect or treatment effect. The incidence and severity of URTS
was significantly greater than baseline at 24 h and 48 h following the race in the
PL group and was also greater than the CJ group (P < 0.05). No URTS were reported in the CJ group whereas 50 % of runners in the PL
group reported URTS at 24 h and 48 h post-Marathon.
Conclusions
This is the first study that provides encouraging evidence of the potential role of
Montmorency cherries in reducing the development of URTS post-Marathon possibly caused
by exercise-induced hyperventilation trauma, and/or other infectious and non-infectious
factors.
Keywords:
Recovery; URTS; Exercise-induced inflammation; Muscle damageBackground
Prolonged and exhaustive exercise is often associated with symptoms and signs of respiratory
mucosal inflammation [1], [2]. The upper respiratory tract symptoms (URTS) usually seen following prolonged and
exhaustive exercise [3], [4] have conventionally been attributed to a transient depression of the innate and adaptive
immunity that eventually progresses into infection [5]. However, recent studies that examined the aetiology of URTS following Marathon running
reported that half or more than two-thirds of symptomatic cases were attributable
to inflammation [6] and/or allergy [7]. This non-infectious hypothesis can be further supported due to the fact, episodes
of URTS in athletes are not characterised by usual seasonal patterns and show an unusual
short-term duration [8]. Exercise-induced airway inflammation, common in endurance athletes [1], [9]-[11] can be mediated by a number of factors including the synergistic effect of hyperventilation
trauma [2], [12], oxidative stress [13] and inhaled allergens and pollutants [7], [10], [14].
Exercise has shown to up-regulate the chemotactic cytokine expression in the airways
[15] causing inflammation, allergic reactions in bronchi, increasing the likelihood of
bronchoconstriction and possibly imitating symptoms that resemble respiratory infections
[8]. For example, interleukin-8 (IL-8) has been implicated in pulmonary inflammation
and hyper-responsiveness under acute oxidative stress [16], [17]. Previous studies have shown a unanimous increase in IL-8 following prolonged and
exhaustive exercise [18], [19]. IL-8 is known to be a potent mediator of chemotaxis, and activates neutrophils resulting
in the generation of reactive oxygen species (ROS) [20], which might lead to pulmonary inflammation and trauma [13]. Neutrophils increase markedly post-Marathon [19], [21], and pulmonary inflammation is characterised by the migration and activation of neutrophils
into the airways [22]. Increased neutrophils in induced sputum post-Marathon have been reported in healthy
athletes [1].
Tart Montmorency cherries are purported to be high in numerous phytochemicals, such
as anthocyanins, and other polyphenolic compounds such as quercetin that possess anti-inflammatory
and anti-oxidative properties [23], [24]. Growing interest in these functional foods has gained momentum in recent years and
there is a mounting body of evidence to suggest Montmorency cherries can facilitate
exercise recovery [24]-[28]; this is likely attributable to the increased bioavailability of these anti-inflammatory
and anti-oxidative phytochemicals following ingestion [29], [30]. In a recent addition to the literature, Bell et al.[24] showed that in trained cyclists, consumption of a Montmorency cherry concentrate
(in comparison to a calorific matched placebo) resulted in a reduction in lipid hyperoxides
and a concomitant reduction in inflammation (IL-6 and C-reactive protein) following
repeated days strenuous cycling. Additionally, polyphenols such as quercetin (also
found in Montmorency cherries), modulate the expression of transcription nuclear factor-kappa
B (NF-kappaB), [31], [32], which may in turn decreased the exercised-induced IL-6 production by an attenuation
of cytokine transcription for IL-6. Previous studies have also shown these polyphenols
to reduce other inflammatory biomarkers such as tumor necrosis factor alpha [32], [33], and macrophage inflammatory protein [33]. Consequently, it is conceivable that the anti-inflammatory and anti-oxidative potential
of Montmorency cherries could attenuate the exercise-induced ‘stress’ response, immunity
and URTS. Therefore, the aim of the current pilot study was to explore the possibility
that Montmorency CJ supplementation before and following Marathon running could modulate
markers of stress, immunity and self-reported upper respiratory tract symptoms.
