Victoria Manning

Bio: Victoria Manning is an academic researcher from Imperial College London. The author has contributed to research in topics: Arthroplasty & Hip resurfacing. The author has an hindex of 9, co-authored 20 publications receiving 1718 citations. Previous affiliations of Victoria Manning include St George's, University of London & King's College London.

Mental fatigue impairs physical performance in humans

Abstract: Mental fatigue is a psychobiological state caused by prolonged periods of demanding cognitive activity. Although the impact of mental fatigue on cognitive and skilled performance is well known, its...

Mental fatigue impairs physical performance in humans

Abstract: Mental fatigue is a psychobiological state caused by prolonged periods of demanding cognitive activity. Although the impact of mental fatigue on cognitive and skilled performance is well known, its effect on physical performance has not been thoroughly investigated. In this randomized crossover study, 16 subjects cycled to exhaustion at 80% of their peak power output after 90 min of a demanding cognitive task (mental fatigue) or 90 min of watching emotionally neutral documentaries (control). After experimental treatment, a mood questionnaire revealed a state of mental fatigue (P = 0.005) that significantly reduced time to exhaustion (640 +/- 316 s) compared with the control condition (754 +/- 339 s) (P = 0.003). This negative effect was not mediated by cardiorespiratory and musculoenergetic factors as physiological responses to intense exercise remained largely unaffected. Self-reported success and intrinsic motivation related to the physical task were also unaffected by prior cognitive activity. However, mentally fatigued subjects rated perception of effort during exercise to be significantly higher compared with the control condition (P = 0.007). As ratings of perceived exertion increased similarly over time in both conditions (P < 0.001), mentally fatigued subjects reached their maximal level of perceived exertion and disengaged from the physical task earlier than in the control condition. In conclusion, our study provides experimental evidence that mental fatigue limits exercise tolerance in humans through higher perception of effort rather than cardiorespiratory and musculoenergetic mechanisms. Future research in this area should investigate the common neurocognitive resources shared by physical and mental activity.

Education, Self‐Management, and Upper Extremity Exercise Training in People With Rheumatoid Arthritis: A Randomized Controlled Trial

Abstract: Objective To evaluate the effectiveness of a brief supervised education, self-management, and global upper extremity exercise training program, supplementing a home exercise regimen, for people with rheumatoid arthritis (RA; the Education, Self-Management, and Upper Extremity Exercise Training in People with Rheumatoid Arthritis [EXTRA] program). Methods Adults with RA of ≤5 years' duration were randomized to receive either usual care or the EXTRA program comprising 4 (1-hour) group education, self-management, and global upper extremity exercise training sessions supplementing the first 2 weeks of a 12-week individualized, functional home exercise regimen in addition to usual care. Outcome measures were assessed at baseline, 12 weeks (primary end point), and 36 weeks and included the Disabilities of the Arm, Shoulder, and Hand questionnaire (primary outcome measure), the Grip Ability Test, handgrip strength (N), the Arthritis Self-Efficacy Scale (pain, function, and symptoms subscales), and the 28-joint Disease Activity Score. Results One hundred eight participants (26 men, mean ± SD age 55 ± 15 years, mean ± SD disease duration 20 ± 19 months) were randomized to receive either usual care (n = 56) or the EXTRA program (n = 52). At 12 weeks, there was a significant between-group difference in the mean change in disability (−6.8 [95% confidence interval (95% CI) −12.6, −1.0]; P = 0.022), function (−3.0 [95% CI −5.0, −0.5]; P = 0.011), nondominant handgrip strength (31.3N [95% CI 9.8, 52.8]; P = 0.009), self-efficacy (10.5 [95% CI 1.6, 19.5]; P = 0.021 for pain and 9.3 [95% CI 0.5, 18.2]; P = 0.039 for symptoms), and disease activity (−0.7 [95% CI −1.4, 0.0]; P = 0.047), all favoring the EXTRA program. Conclusion The EXTRA program improves upper extremity disability, function, handgrip strength, and self-efficacy in people with RA, with no adverse effects on disease activity.

Unicompartmental knee arthroplasty enables near normal gait at higher speeds, unlike total knee arthroplasty.

Abstract: Top walking speed (TWS) was used to compare UKA with TKA. Two groups of 23 patients, well matched for age, gender, height and weight and radiological severity were recruited based on high functional scores, more than twelve months post UKA or TKA. These were compared with 14 preop patients and 14 normal controls. Their gait was measured at increasing speeds on a treadmill instrumented with force plates. Both arthroplasty groups were significantly faster than the preop OA group. TKA patients walked substantially faster than any previously reported series of knee arthroplasties. UKA patients walked 10% faster than TKA, although not as fast as the normal controls. Stride length was 5% greater and stance time 7% shorter following UKA — both much closer to normal than TKA. Unlike TKA, UKA enables a near normal gait one year after surgery.

The gait of patients with one resurfacing and one replacement hip: a single blinded controlled study

Abstract: Purposes Post arthroplasty gait analysis has up till now been performed on subjects walking slowly on flat ground rather than challenging them at faster speeds or walking uphill. We therefore asked: (1) Is there a measurable difference in the performance of hip resurfacing arthroplasty (HRA) and total hip arthroplasty (THA) limbs at patients’ self-determined fastest walking speeds and steepest inclines? and (2) Is there a relationship between the observed differences between the gait of HRA and THA implanted limbs and patient walking speeds and inclines.

High-intensity interval training, solutions to the programming puzzle: Part I: cardiopulmonary emphasis.

Abstract: High-intensity interval training (HIT), in a variety of forms, is today one of the most effective means of improving cardiorespiratory and metabolic function and, in turn, the physical performance of athletes. HIT involves repeated short-to-long bouts of rather high-intensity exercise interspersed with recovery periods. For team and racquet sport players, the inclusion of sprints and all-out efforts into HIT programmes has also been shown to be an effective practice. It is believed that an optimal stimulus to elicit both maximal cardiovascular and peripheral adaptations is one where athletes spend at least several minutes per session in their 'red zone,' which generally means reaching at least 90% of their maximal oxygen uptake (VO2max). While use of HIT is not the only approach to improve physiological parameters and performance, there has been a growth in interest by the sport science community for characterizing training protocols that allow athletes to maintain long periods of time above 90% of VO2max (T@VO2max). In addition to T@VO2max, other physiological variables should also be considered to fully characterize the training stimulus when programming HIT, including cardiovascular work, anaerobic glycolytic energy contribution and acute neuromuscular load and musculoskeletal strain. Prescription for HIT consists of the manipulation of up to nine variables, which include the work interval intensity and duration, relief interval intensity and duration, exercise modality, number of repetitions, number of series, as well as the between-series recovery duration and intensity. The manipulation of any of these variables can affect the acute physiological responses to HIT. This article is Part I of a subsequent II-part review and will discuss the different aspects of HIT programming, from work/relief interval manipulation to the selection of exercise mode, using different examples of training cycles from different sports, with continued reference to T@VO2max and cardiovascular responses. Additional programming and periodization considerations will also be discussed with respect to other variables such as anaerobic glycolytic system contribution (as inferred from blood lactate accumulation), neuromuscular load and musculoskeletal strain (Part II).

High-Intensity Interval Training, Solutions to the Programming Puzzle

Abstract: High-intensity interval training (HIT) is a well-known, time-efficient training method for improving cardiorespiratory and metabolic function and, in turn, physical performance in athletes. HIT involves repeated short (<45 s) to long (2–4 min) bouts of rather high-intensity exercise interspersed with recovery periods (refer to the previously published first part of this review). While athletes have used ‘classical’ HIT formats for nearly a century (e.g. repetitions of 30 s of exercise interspersed with 30 s of rest, or 2–4-min interval repetitions ran at high but still submaximal intensities), there is today a surge of research interest focused on examining the effects of short sprints and all-out efforts, both in the field and in the laboratory. Prescription of HIT consists of the manipulation of at least nine variables (e.g. work interval intensity and duration, relief interval intensity and duration, exercise modality, number of repetitions, number of series, between-series recovery duration and intensity); any of which has a likely effect on the acute physiological response. Manipulating HIT appropriately is important, not only with respect to the expected middle- to long-term physiological and performance adaptations, but also to maximize daily and/or weekly training periodization. Cardiopulmonary responses are typically the first variables to consider when programming HIT (refer to Part I). However, anaerobic glycolytic energy contribution and neuromuscular load should also be considered to maximize the training outcome. Contrasting HIT formats that elicit similar (and maximal) cardiorespiratory responses have been associated with distinctly different anaerobic energy contributions. The high locomotor speed/power requirements of HIT (i.e. ≥95 % of the minimal velocity/power that elicits maximal oxygen uptake [v/p $$ \dot{V} $$ O2max] to 100 % of maximal sprinting speed or power) and the accumulation of high-training volumes at high-exercise intensity (runners can cover up to 6–8 km at v $$ \dot{V} $$ O2max per session) can cause significant strain on the neuromuscular/musculoskeletal system. For athletes training twice a day, and/or in team sport players training a number of metabolic and neuromuscular systems within a weekly microcycle, this added physiological strain should be considered in light of the other physical and technical/tactical sessions, so as to avoid overload and optimize adaptation (i.e. maximize a given training stimulus and minimize musculoskeletal pain and/or injury risk). In this part of the review, the different aspects of HIT programming are discussed, from work/relief interval manipulation to HIT periodization, using different examples of training cycles from different sports, with continued reference to the cardiorespiratory adaptations outlined in Part I, as well as to anaerobic glycolytic contribution and neuromuscular/musculoskeletal load.

Toward a Rational and Mechanistic Account of Mental Effort.

Abstract: In spite of its familiar phenomenology, the mechanistic basis for mental effort remains poorly understood. Although most researchers agree that mental effort is aversive and stems from limitations in our capacity to exercise cognitive control, it is unclear what gives rise to those limitations and why they result in an experience of control as costly. The presence of these control costs also raises further questions regarding how best to allocate mental effort to minimize those costs and maximize the attendant benefits. This review explores recent advances in computational modeling and empirical research aimed at addressing these questions at the level of psychological process and neural mechanism, examining both the limitations to mental effort exertion and how we manage those limited cognitive resources. We conclude by identifying remaining challenges for theoretical accounts of mental effort as well as possible applications of the available findings to understanding the causes of and potential solutions for apparent failures to exert the mental effort required of us.

The effects of mental fatigue on physical performance: a systematic review

Abstract: Mental fatigue is a psychobiological state caused by prolonged periods of demanding cognitive activity. It has recently been suggested that mental fatigue can affect physical performance. Our objective was to evaluate the literature on impairment of physical performance due to mental fatigue and to create an overview of the potential factors underlying this effect. Two electronic databases, PubMed and Web of Science (until 28 April 2016), were searched for studies designed to test whether mental fatigue influenced performance of a physical task or influenced physiological and/or perceptual responses during the physical task. Studies using short (<30 min) self-regulatory depletion tasks were excluded from the review. A total of 11 articles were included, of which six were of strong and five of moderate quality. The general finding was a decline in endurance performance (decreased time to exhaustion and self-selected power output/velocity or increased completion time) associated with a higher than normal perceived exertion. Physiological variables traditionally associated with endurance performance (heart rate, blood lactate, oxygen uptake, cardiac output, maximal aerobic capacity) were unaffected by mental fatigue. Maximal strength, power, and anaerobic work were not affected by mental fatigue. The duration and intensity of the physical task appear to be important factors in the decrease in physical performance due to mental fatigue. The most important factor responsible for the negative impact of mental fatigue on endurance performance is a higher perceived exertion.