Andrew M Jones

University of Exeter | UoE · Department of Sport and Health Sciences

From a physiological perspective, the delineation between steady-state and non-steady-state exercise, also referred to as the maximal metabolic steady state, holds paramount importance for evaluating athletic performance and designing and monitoring training programs. The critical power and the maximal lactate steady state are two widely used indic...

Identification of the power output which separates the heavy intensity exercise domain, wherein steady states in blood [lactate] and pulmonary V̇O 2 are achievable, from the severe intensity domain, wherein they are not, has conceptual and practical value in exercise physiology. Purpose To develop a new method that more closely represents the heav...

Purpose We studied the effect of O 2 supplementation on physiological response to exercise in patients with moderate to severe interstitial lung disease (ILD). Methods 13 patients (age 66 ± 10 yrs., 7 males) with ILD (TLC 71 ± 22% predicted, carbon monoxide diffusion capacity (DLCO) 44 ± 16% predicted) and 13 healthy individuals (age 50 ± 17 yrs.,...

Purpose : This study determined the evolution of performance and pacing for each winner of the men’s Olympic 1500-m running track final from 1924 to 2020. Methods : Data were obtained from publicly available sources. When official splits were unavailable, times from sources such as YouTube were included and interpolated from video records. Final ti...

The nitrate (NO3⁻) reducing bacteria resident in the oral cavity have been implicated as key mediators of nitric oxide (NO) homeostasis and human health. NO3⁻-reducing oral bacteria reduce inorganic dietary NO3⁻ to nitrite (NO2⁻) via the NO3⁻-NO2⁻-NO pathway. Studies of oral NO3⁻-reducing bacteria have typically sampled from either the tongue surfa...

A low carbohydrate, high fat (LCHF) diet in athletes increases fat oxidation but impairs sports performance, potentially due to impaired exercise economy. Dietary nitrate supplementation can improve exercise economy via an increase in nitric oxide production, which is initiated by the reduction of nitrate to nitrite within the oral cavity. This rea...

Interval training is a simple concept that refers to repeated bouts of relatively hard work interspersed with recovery periods of easier work or rest. The method has been used by high-level athletes for over a century to improve performance in endurance-type sports and events such as middle- and long-distance running. The concept of interval traini...

Endurance exercise performance is known to be closely associated with the three physiological pillars of maximal O2 uptake (V̇O2max$\dot{V}_{{\rm O}_{2}{\rm max}}$), economy or efficiency during submaximal exercise, and the fractional utilisation of V̇O2max$\dot{V}_{{\rm O}_{2}{\rm max}}$ (linked to metabolic/lactate threshold phenomena). However,...

Objective The nitrate-nitrite-nitric oxide pathway contributes to blood pressure (BP) regulation in humans. However, it is unknown if the pathway alters arterial haemodynamic parameters derived from reservoir-excess pressure analysis. We therefore determined whether an enhancement/disruption of nitrate-nitrite-nitric oxide pathway by dietary nitrat...

Dietary nitrate (NO3-) supplementation can enhance nitric oxide (NO) bioavailability and lower blood pressure (BP) in humans. The nitrite concentration ([NO2-]) in the plasma is the most commonly used biomarker of increased NO availability. However, it is unknown to what extent changes in other NO congeners, such as S-nitrosothiols (RSNOs), and in...

Scientific interest in pacing goes back >100 years. Contemporary interest, both as a feature of athletic competition and as a window into understanding fatigue, goes back >30 years. Pacing represents the pattern of energy use designed to produce a competitive result while managing fatigue of different origins. Pacing has been studied both against t...

The purpose of this study was to investigate effects of concurrent and independent administration of dietary nitrate (NO3-), administered as NO3--rich beetroot juice (BR; ~12.4 mmol of NO3-), and N-acetylcysteine (NAC; 70 mg·kg-1) on physiological responses during prolonged exercise and subsequent high-intensity exercise tolerance. Sixteen recreati...

This study tested the hypothesis that the increases in salivary and plasma [NO2−] after dietary NO3− supplementation would be greater when oral temperature and pH were independently elevated, and increased further when oral temperature and pH were elevated concurrently. Seven healthy males (mean ± SD, age 23 ± 4 years) ingested 70 mL of beetroot ju...

Aim: Dietary nitrate (NO3 - ) supplementation increases nitric oxide bioavailability and can enhance exercise performance. We investigated the distribution and metabolic fate of ingested NO3 - at rest and during exercise with a focus on skeletal muscle. Methods: In a randomised, crossover study, ten healthy volunteers consumed 12.8 mmol 15 N-lab...

Purpose: This study aimed to: 1) examine the accuracy with which W' reconstitution (W'REC) is estimated by the W' balance (W'BAL) models following a 3-min all-out test (3MT); 2) determine the effects of a 3MT on the power-duration relationship, and; 3) assess whether accounting for changes in the power-duration relationship during exercise improve...

Dietary nitrate (NO3-) supplementation, which has ergogenic effects during exercise, increases nitric oxide (NO) bioavailability primarily through oral bacterial reduction of NO3- to nitrite (NO2-), which acts as a NO precursor in circulation and tissues. Novel evidence suggests that NO3- reduction can also occur via xanthine oxidoreductase (XOR),...

Skeletal muscle is one of the most dynamic metabolic organs as evidenced by increases in metabolic rate of >150-fold from rest to maximal contractile activity. Because of limited intracellular stores of ATP, activation of metabolic pathways is required to maintain the necessary rates of ATP re-synthesis during sustained contractions. During the ver...

Introduction Dietary inorganic nitrate is a popular nutritional supplement, which increases nitric oxide bioavailability and may improve exercise performance. Despite over a decade of research into the effects of dietary nitrate supplementation during exercise there is currently no expert consensus on how, when and for whom this compound could be r...

Dietary nitrate (NO3-) supplementation can reduce the oxygen cost of submaximal exercise, but this has not been reported consistently. We hypothesised that the number of step transitions to moderate-intensity exercise, and corresponding effects on the signal-to-noise ratio for pulmonary V˙ O2, may be important in this regard. Twelve recreationally...

Purpose: Peak power output ([Formula: see text]peak) in an incremental exercise test (EXT) is considered an important predictor of performance for cyclists. However, [Formula: see text]peak is protocol dependent. The purpose of this study was to model the effect of EXT design on [Formula: see text]peak. Methods: An adapted version of a previousl...

Dietary nitrate (NO3⁻) ingestion can be beneficial for health and exercise performance. Recently, based on animal and limited human studies, a skeletal muscle NO3⁻ reservoir has been suggested to be important in whole body nitric oxide (NO) homeostasis. The purpose of this study was to determine the time course of changes in human skeletal muscle N...

Objective Pulmonary oxygen uptake (V̇O2) kinetics measured during initiation of exercise mirror energetic transition during daily activity. The aim of this study was to elucidate the pathophysiological mechanisms of exercise limitation of patients with chronic ilio-femoral vein obstruction after deep vein thrombosis by measuring V̇O2 kinetics compa...

Purpose: We tested the hypotheses that a highly cushioned running shoe (HCS) would: 1) improve incremental exercise performance and reduce the oxygen cost (Oc) of submaximal running; and 2) attenuate the deterioration in Oc elicited by muscle damage consequent to a downhill run. Methods: Thirty-two recreationally-active participants completed an...

The metabolic boundary separating the heavy-intensity and severe-intensity exercise domains is of scientific and practical interest but there is controversy concerning whether the maximal lactate steady state (MLSS) or critical power (synonymous with critical speed, CS) better represents this boundary. We measured the running speeds at MLSS and CS...

Non-enzymatic nitric oxide (NO) generation via the reduction of nitrate and nitrite ions, along with remarkably high levels of nitrate ions in skeletal muscle, have been recently described. Skeletal muscle nitrate storage may be critical for maintenance of NO homeostasis in healthy ageing and nitrate supplementation may be useful for treatment of s...

Dietary nitrate supplementation has been shown to reduce pulmonary O2 uptake during submaximal exercise and enhance exercise performance. However, the effects of nitrate supplementation on local metabolic and haemodynamic regulation in contracting human skeletal muscle remain unclear. To address this, eight healthy young male sedentary subjects wer...

The best possible finishing time for a runner competing in distance track events can be estimated from their critical speed (CS) and the finite amount of energy that can be expended above CS (D'). During tactical races with variable pacing, the runner with the 'best' combination of CS and D' and, therefore, the fastest estimated finishing time prio...

Critical power (CP) delineates the heavy and severe exercise intensity domains, and sustained work rates above CP result in an inexorable progression of oxygen uptake to a maximal value and, subsequently, the limit of exercise tolerance. The finite work capacity above CP, W′, is defined by the curvature constant of the power-duration relationship....

Given the importance of exercise economy to endurance performance, we implemented two strategies purported to reduce the oxygen cost of exercise within a 4 week training camp in 21 elite male race walkers. Fourteen athletes undertook a crossover investigation with beetroot juice (BRJ) or placebo (PLA) [2 d preload, 2 h pre-exercise + 35 min during...

PURPOSE: Performance in running events, such as 1-Mile World Records (WR), depends both on having and effectively using energetic resources. Although often understood in terms of physiological capacity based on the Joyner model, the Critical Speed/D’ model is an alternative method of accounting for energetic capacity and use, based on prior perform...

BACKGROUND: Some recovery strategies are needed to reduce or eliminate the effect of negative symptoms caused by exercise. OBJECTIVE: The aim of this study was to determine the effect of different types of recovery after single-bout strength exercises on biomarkers of muscle damage, cytokine release and lactate elimination. METHODS: Following famil...

There is scientific and legal controversy about recent technological advances in performance running shoes that reduce the energetic cost of running and may provide a distinct competitive advantage. To better understand the potential performance-enhancing effects of technological advancements in marathon racing shoes, we examined the finishing time...

Prolonged exposure to microgravity during spaceflights leads to severe deterioration in the physical performance of astronauts. To understand the effectiveness of existing in-flight daily countermeasures and to plan exercise onboard the International Space Station, we compared supine treadmill running to traditional upright treadmill running on ear...

Ingested inorganic nitrate (NO3⁻) has multiple effects in the human body including vasodilation, inhibition of platelet aggregation, and improved skeletal muscle function. The functional effects of oral NO3⁻ involve the in vivo reduction of NO3⁻ to nitrite (NO2⁻) and thence to nitric oxide (NO). However, the potential involvement of S-nitrosothiol...

Many oral bacteria reduce inorganic nitrate, a natural part of a vegetable-rich diet, into nitrite that acts as a precursor to nitric oxide, a regulator of vascular tone and neurotransmission. Aging is hallmarked by reduced nitric oxide production with associated detriments to cardiovascular and cognitive function. This study applied a systems-leve...

There is scientific and legal controversy about recent technological advances in performance running shoes that reduce the energetic cost of running and may provide a distinct competitive advantage. To better understand the potential performance-enhancing effects of Nikes pioneering marathon racing shoes, we examined the finishing times and racing...

The requirements of running a 2 hour marathon have been extensively debated but the actual physiological demands of running at ~21.1 km/h have never been reported. We therefore conducted laboratory-based physiological evaluations and measured running economy (O2 cost) while running outdoors at ~21.1 km/h, in world-class distance runners as part of...

Nitric oxide (NO) is a gaseous signaling molecule that plays an important role in myriad physiological processes including the regulation of vascular tone, neurotransmission, mitochondrial respiration and skeletal muscle contractile function. NO may be produced via the canonical NOS-catalyzed oxidation of l-arginine and also by the sequential reduc...

Sickle cell disease (SCD) causes exercise intolerance likely due to impaired skeletal muscle function and low nitric oxide (NO) bioavailability. Dietary nitrate improves hemodynamic and metabolic control during exercise in humans and animals. The purpose of this investigation was to assess the impact of nitrate supplementation on exercise capacity...

Aims: To investigate the effects of supplementation with high-nitrate and low-nitrate vegetables on plasma nitrate and nitrite concentrations, blood pressure and the oxygen demand of moderate-intensity exercise. Study Design: A randomized, cross-over design. Place and Duration of Study: Sport and Health Sciences, College of Life and Environmental S...

Despite emerging evidence linking pain sensation to exercise performance (Mauger et al., 2010), the role of pain sensation in exercise-induced fatigue has received limited research attention. Paracetamol (or acetaminophen, ACT) is a non-specific inhibitor of the cyclooxygenase enzymes. These enzymes synthesise prostaglandins, which sensitise group...

PurposeThis study tested the hypothesis that a novel, audio-visual-directed, home-based exercise training intervention would be effective at improving cardiometabolic health and mental well-being in inactive premenopausal women.Methods Twenty-four inactive premenopausal women (39 ± 10 years) were randomly assigned to an audio-visual-directed exerci...

In a previous study 15 days of dietary nitrate/nitrite (NO 3 ⁻ /NO 2 ⁻ ) supplementation was associated with a lower V̇O 2p gain (ΔV̇O 2p /ΔPower Output; PO) in the moderate (MOD) intensity exercise domain and a higher V̇O 2p gain for exercise above lactate threshold (θ L ) 1 . It remains unclear how V̇O 2p gain is affected within the heavy‐ (HVY;...

Critical Power (CP) separates the heavy and severe exercise domains, and work above CP (defined as W′) results in an inexorable progression to maximal oxygen uptake and rise in blood lactate concentration to fatigue. The thermoregulatory demands accompanying a rise in body core temperature (T c ) compounded with the cardiovascular challenges presen...

We tested the hypothesis that acute supplementation with nitrate (NO3-)-rich beetroot juice (BR) would improve quadriceps muscle oxygenation, pulmonary oxygen uptake ( O2) kinetics and exercise tolerance (Tlim) in normoxia and that these improvements would be augmented in hypoxia and attenuated in hyperoxia. In a randomized, double-blind, cross-ove...

We reinforce the key messages in our earlier review paper that critical power, rather than maximal lactate steady state, provides the better index for defining steady‐state vs non‐steady state physiological behaviour during exercise.

Key points Dietary nitrate supplementation increases plasma nitrite concentration, which provides an oxygen‐independent source of nitric oxide and can delay skeletal muscle fatigue. Nitrate supplementation has been shown to increase myofibre calcium release and force production in mouse skeletal muscle during contractions at a supra‐physiological o...

Key points Nitric oxide (NO), a potent vasodilator and a regulator of many physiological processes, is produced in mammals both enzymatically and by reduction of nitrite and nitrate ions. We have previously reported that, in rodents, skeletal muscle serves as a nitrate reservoir, with nitrate levels greatly exceeding those in blood or other interna...

We tested the hypotheses that the parameters of the power-duration relationship, estimated as the end-test power (EP) and work done above EP (WEP) during a 3-min all out exercise test (3MT), would be reduced progressively following 40 min, 80 min and 2 h of heavy-intensity cycling, and that carbohydrate (CHO) ingestion would attenuate the reduction...

Exhaustive single-leg exercise has been suggested to reduce time to task failure (Tlim) during subsequent exercise in the contralateral leg by exacerbating central fatigue development. We investigated the influence of acetaminophen (ACT), an analgesic which may blunt central fatigue development, on Tlim during single-leg exercise completed both wit...

Abstract The maximal lactate steady state (MLSS) and the critical power (CP) are two widely used indices of the highest oxidative metabolic rate that can be sustained during continuous exercise and are often considered to be synonymous. However, while perhaps having similarities in principle, methodological differences in the assessment of these pa...

It is not clear how the parameters of the power-duration relationship [critical power (CP) and W'] are influenced by the performance of prolonged endurance exercise. We used severe-intensity prediction trials (conventional protocol) and the 3-min all-out test (3MT) to measure CP and W' following 2 h of heavy-intensity cycling exercise and took musc...

Distance events in Athletics include cross country, 10,000-m track race, half-marathon and marathon road races, and 20- and 50-km race walking events over different terrain and environmental conditions. Race times for elite performers span ∼26 min to >4 hr, with key factors for success being a high aerobic power, the ability to exercise at a large...