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1.
Res Involv Engagem ; 8(1): 74, 2022 Dec 23.
Article in English | MEDLINE | ID: mdl-36550509

ABSTRACT

BACKGROUND: Using the technique of co-production to develop research is considered good practice. Co-production involves the public, practitioners and academics working together as equals throughout a research project. Co-production may help develop alternative ways of delivering care for older adults that are acceptable to those who live and work in care homes. However, guidance about applying co-production approaches in this context is lacking. This scoping review aims to map co-production approaches used in care homes for older adults in previous research to support the inclusion of residents and care staff as equal collaborators in future studies. METHODS: A scoping review was conducted using the Joanna Briggs Institute scoping review methodology. Seven electronic databases were searched for peer-reviewed primary studies using co-production approaches in care home settings for older adults. Studies were independently screened against eligibility criteria by two reviewers. Citation searching was completed. Data relating to study characteristics, co-production approaches used, including any barriers and facilitators, was charted by one reviewer and checked by another. Data was summarised using tables and diagrams with an accompanying narrative description. A collaborator group of care home and health service representatives were involved in the interpretation of the findings from their perspectives. RESULTS: 19 studies were selected for inclusion. A diverse range of approaches to co-production and engaging key stakeholders in care home settings were identified. 11 studies reported barriers and 13 reported facilitators affecting the co-production process. Barriers and facilitators to building relationships and achieving inclusive, equitable and reciprocal co-production were identified in alignment with the five NIHR principles. Practical considerations were also identified as potential barriers and facilitators. CONCLUSION: The components of co-production approaches, barriers and facilitators identified should inform the design of future research using co-production approaches in care homes. Future studies should be explicit in reporting what is meant by co-production, the methods used to support co-production, and steps taken to enact the principles of co-production. Sharing of key learning is required to support this field to develop. Evaluation of co-production approaches, including participants' experiences of taking part in co-production processes, are areas for future research in care home settings.


Co-production involves people from different backgrounds working together as equals throughout a research project. Co-production may be a useful approach to help ensure that research in care homes focuses on approaches that are important and agreeable to older people and staff. A wide range of research and guidance about co-production has been published but there is limited guidance about how to do co-production in care homes. We carried out a review that involved pulling together previous research that used co-production in care homes for older adults. We looked at published research studies to learn about: Key components of the strategies used to achieve co-production, How care home residents and care home staff were involved, What helped or made co-production difficult to achieve. A collaborator group including representatives from care homes and healthcare services were involved in this research. They helped decide what was most important about the results.We found 19 published research articles that used co-production in care homes. The strategies used in the articles differed. There were also differences in how care home residents and staff were involved in co-production. Factors that helped people involved to work together in an inclusive and equal way were identified. At the same time, there were also many challenges.These results should be used to design future research using co-production in care homes. Future studies should clearly report what is meant by co-production, the strategies used and key learning points. Evaluation of co-production and the experiences of people involved is needed.

2.
Public Health ; 197: 11-18, 2021 Aug.
Article in English | MEDLINE | ID: mdl-34271270

ABSTRACT

OBJECTIVES: Falls in older adults cause significant morbidity and mortality and incur cost to health and care services. The Falls Management Exercise (FaME) programme is a 24-week intervention for older adults that, in clinical trials, improves balance and functional strength and leads to fewer falls. Similar but more modest outcomes have been found when FaME is delivered in routine practice. Understanding the degree to which the programme is delivered with fidelity is important if 'real-world' delivery of FaME is to achieve the same magnitude of outcome as in clinical trials. The objective of this study was to examine the implementation fidelity of FaME when delivered in the community to inform quality improvement strategies that maximise programme effectiveness. STUDY DESIGN: A mixed methods implementation study of FaME programme delivery. METHODS: Data from programme registers, expert observations of FaME classes, and semistructured interviews with FaME instructors were triangulated using a conceptual framework for implementation fidelity. Quantitative data were analysed using descriptive statistics. Interviews were transcribed verbatim and analysed using thematic analysis. RESULTS: In total, 356 participants enrolled on 29 FaME programmes, and 143 (40%) participants completed at least 75% of the classes within a programme. Observations showed that 72%-78% of programme content was delivered, and 80%-84% quality criteria were met. Important content that was most often left out included home exercises, Tai Chi moves, and floor work, whereas quality items most frequently missed out included asking about falls in the previous week, following up attendance absence and explaining the purpose of exercises. Only 24% of class participants made the expected strength training progression. Interviews with FaME instructors helped explain why elements of programme content and quality were not delivered. Strategies for improving FaME delivery were established and helped to maintain quality and fidelity. CONCLUSIONS: FaME programmes delivered in the 'real world' can be implemented with a high degree of fidelity, although important deviations were found. Facilitation strategies could be used to further improve programme fidelity and maximise participant outcomes.


Subject(s)
Exercise , Resistance Training , Aged , Exercise Therapy , Humans , Program Evaluation
3.
BMC Med Res Methodol ; 20(1): 46, 2020 02 27.
Article in English | MEDLINE | ID: mdl-32106827

ABSTRACT

BACKGROUND: Trials are at risk of contamination bias which can occur when participants in the control group are inadvertently exposed to the intervention. This is a particular risk in rehabilitation studies where it is easy for trial interventions to be either intentionally or inadvertently adopted in control settings. The Falls in Care Homes (FinCH) trial is used in this paper as an example of a large randomised controlled trial of a complex intervention to explore the potential risks of contamination bias. We outline the FinCH trial design, present the potential risks from contamination bias, and the strategies used in the design of the trial to minimise or mitigate against this. The FinCH trial was a multi-centre randomised controlled trial, with embedded process evaluation, which evaluated whether systematic training in the use of the Guide to Action Tool for Care Homes reduced falls in care home residents. Data were collected from a number of sources to explore contamination in the FinCH trial. Where specific procedures were adopted to reduce risk of, or mitigate against, contamination, this was recorded. Data were collected from study e-mails, meetings with clinicians, research assistant and clinician network communications, and an embedded process evaluation in six intervention care homes. During the FinCH trial, there were six new falls prevention initiatives implemented outside the study which could have contaminated our intervention and findings. Methods used to minimise contamination were: cluster randomisation at the level of care home; engagement with the clinical community to highlight the risks of early adoption; establishing local collaborators in each site familiar with the local context; signing agreements with NHS falls specialists that they would maintain confidentiality regarding details of the intervention; opening additional research sites; and by raising awareness about the importance of contamination in research among participants. CONCLUSION: Complex rehabilitation trials are at risk of contamination bias. The potential for contamination bias in studies can be minimized by strengthening collaboration and dialogue with the clinical community. Researchers should recognise that clinicians may contaminate a study through lack of research expertise.


Subject(s)
Accident Prevention/methods , Accidental Falls/prevention & control , Exercise Therapy/methods , Homes for the Aged/statistics & numerical data , Nursing Homes/statistics & numerical data , Aged , Humans , Outcome Assessment, Health Care/methods , Outcome Assessment, Health Care/statistics & numerical data , Randomized Controlled Trials as Topic , Risk Factors
4.
BMJ ; 329(7479): 1372-5, 2004 Dec 11.
Article in English | MEDLINE | ID: mdl-15564229

ABSTRACT

OBJECTIVE: To evaluate an occupational therapy intervention to improve outdoor mobility after stroke. DESIGN: Randomised controlled trial. SETTING: General practice registers, social services departments, a primary care rehabilitation service, and a geriatric day hospital. PARTICIPANTS: 168 community dwelling people with a clinical diagnosis of stroke in previous 36 months: 86 were allocated to the intervention group and 82 to the control group. INTERVENTIONS: Leaflets describing local transport services for disabled people (control group) and leaflets with assessment and up to seven intervention sessions by an occupational therapist (intervention group). MAIN OUTCOME MEASURES: Responses to postal questionnaires at four and 10 months: primary outcome measure was response to whether participant got out of the house as much as he or she would like, and secondary outcome measures were response to how many journeys outdoors had been made in the past month and scores on the Nottingham extended activities of daily living scale, Nottingham leisure questionnaire, and general health questionnaire. RESULTS: Participants in the treatment group were more likely to get out of the house as often as they wanted at both four months (relative risk 1.72, 95% confidence interval 1.25 to 2.37) and 10 months (1.74, 1.24 to 2.44). The treatment group reported more journeys outdoors in the month before assessment at both four months (median 37 in intervention group, 14 in control group: P < 0.01) and 10 months (median 42 in intervention group, 14 in control group: P < 0.01). At four months the mobility scores on the Nottingham extended activities of daily living scale were significantly higher in the intervention group, but there were no significant differences in the other secondary outcomes. No significant differences were observed in these measures at 10 months. CONCLUSION: A targeted occupational therapy intervention at home increases outdoor mobility in people after stroke.


Subject(s)
Occupational Therapy/methods , Stroke Rehabilitation , Activities of Daily Living , Aged , Female , Home Care Services , Humans , Male , Quality of Life , Risk Factors , Treatment Outcome
5.
Clin Rehabil ; 18(6): 703-8, 2004 Sep.
Article in English | MEDLINE | ID: mdl-15473122

ABSTRACT

INTRODUCTION: Many people who have had a stroke want to get out of their house more often. This study explored attitudes and barriers to the use of transport with the aim of informing rehabilitation. METHOD: Semi-structured interview study of 24 community-dwelling people who had had a stroke, purposively sampled to find people with a variety of recent experiences of transport. Interviews were taped and transcribed. Analysis was by constant-comparative methodology, to develop emerging themes and concepts. RESULTS: Interviewees wanted to travel for specific purposes but also for its own sake. Many could no longer use their car. This gave them less flexibility to travel and reduced their autonomy. Barriers to using alternative forms of transport were fear of injury or embarrassment from falling, an associated lack of confidence, inadequate information about transport services, perceptions about the cost of taxis and pavement vehicles (scooters) and environmental factors such as the weather. Those who could drive, or who lived with someone who did, gave the most positive descriptions of transport use. Those reliant on family or friends felt they could ask only for help getting to health-related appointments and those who used specialist transport services provided the most negative descriptions of transport. CONCLUSIONS: Many of the barriers to transport use after stroke may be amenable to intervention. An intervention package capable of re-enabling people to drive or be driven, to use a pavement scooter safely, to provide information about the alternatives and to encourage best use of public transport is worth developing.


Subject(s)
Stroke Rehabilitation , Activities of Daily Living , Aged , Automobile Driving , Female , Humans , Interviews as Topic , Male , Transportation , Weather
6.
J Am Chem Soc ; 126(37): 11436-7, 2004 Sep 22.
Article in English | MEDLINE | ID: mdl-15366879

ABSTRACT

Proton NMR imaging was used to investigate in situ the distribution of water in a polymer electrolyte membrane fuel cell operating on H2 and O2. In a single experiment, water was monitored in the gas flow channels, the membrane electrode assembly, and in the membrane surrounding the catalysts. Radial gradient diffusion removes water from the catalysts into the surrounding membrane. This research demonstrates the strength of 1H NMR microscopy as an aid for designing fuel cells to optimize water management.

7.
Clin Rehabil ; 17(3): 249-55, 2003 May.
Article in English | MEDLINE | ID: mdl-12735531

ABSTRACT

OBJECTIVE: To undertake a detailed analysis of therapy provided in a multicentred randomized controlled trial of activities of daily living (ADL) and leisure (TOTAL), testing the hypothesis that specific interventions given in the trial affected specific aspects of outcome. SUBJECTS: Three hundred and nine stroke patients who had been randomly allocated to receive either occupational therapy aimed at ADL activities (n = 156) or leisure (n = 153). MEASURES: Number, duration and type of activity undertaken per patient. Barthel Index, Extended Activities of Daily Living Scale (EADL) and Nottingham Leisure Questionnaire (NLQ) six months after entry to the study. METHOD: Activities that had been used in treatment were coded and categorized. Frequently used activities identified. These activities were matched to items from the six-month outcome measures. Patient independence in these outcome items was compared between the leisure and ADL groups. RESULTS: Three hundred and nine therapy record forms were returned. Patients received a median of ten sessions with a median duration of 55 minutes. The ADL group received significantly more, mobility training, transfer training, cleaning, dressing, cooking and bathing training (chi-squared, p < 0.05). Sport, creative activities, games, hobbies, gardening, entertainment and shopping were used significantly more in the leisure group (chi-squared, p < 0.05) than the ADL group. Fifteen items from the outcome measures were identified as specific to these interventions. There were no statistically significant differences in outcome on these 15 items between the ADL and leisure groups (chi-squared, p > 0.05). CONCLUSIONS: We found no evidence that specific ADL or leisure interventions led to improvements in specific relevant outcomes. We believe that these findings should prompt a review of the relationship between process and outcome of occupational therapy.


Subject(s)
Activities of Daily Living , Leisure Activities , Occupational Therapy , Stroke Rehabilitation , Humans , Medical Records , Multicenter Studies as Topic , Randomized Controlled Trials as Topic , Treatment Outcome
8.
Article in English | MEDLINE | ID: mdl-11282321

ABSTRACT

Despite equivocal findings about the benefit of altitude training, current theory dictates that the best approach is to spend several weeks living at > or =2500 m but training near sea level. This paper summarizes six studies in which we used simulated altitude (normobaric hypoxia) to examine: (i) the assumption that moderate hypoxia compromises training intensity (two studies); and (ii) the nature of physiological adaptations to sleeping in moderate hypoxia (four studies). When submaximal exercise was >55% of sea level maximum oxygen uptake (VO2max), 1800 m simulated altitude significantly increased heart rate, blood lactate and perceived exertion of skiers. In addition, cyclists self-selected lower workloads during high-intensity exercise in hypoxia (2100 m) than in normoxia. Consequently, our findings partially confirm the rationale for 'living high, training low'. In the remaining four studies, serum erythropoietin increased 80% in the early stages of hypoxic exposure, but the reticulocyte response did not significantly exceed that of control subjects. There was no significant increase in haemoglobin mass (Hb(mass)) and VO2max tended to decrease. Performance in exercise tasks lasting approximately 4 min showed a non-significant trend toward improvement (1.0+/-0.4% vs. 0.1+/-0.4% for a control group; P=0.13 for group x time interaction). We conclude that sleeping in moderate hypoxia (2650-3000 m) for up to 23 days may offer practical benefit to elite athletes, but that any effect is not likely due to increased Hb(mass) or VO2max.


Subject(s)
Adaptation, Physiological , Altitude , Exercise , Sports , Adult , Erythrocyte Count , Erythrocyte Volume , Erythropoietin/blood , Exercise Tolerance , Female , Heart Rate , Hemodynamics , Humans , Hypoxia/physiopathology , Male , Oxygen/pharmacokinetics , Sleep/physiology
9.
Clin Rehabil ; 15(1): 42-52, 2001 Feb.
Article in English | MEDLINE | ID: mdl-11237160

ABSTRACT

OBJECTIVE: To evaluate the effects of leisure therapy and conventional occupational therapy (OT) on the mood, leisure participation and independence in activities of daily living (ADL) of stroke patients 6 and 12 months after hospital discharge. DESIGN: Multicentre randomized controlled trial. SETTING AND PARTICIPANTS: Four hundred and sixty-six stroke patients from five UK centres. MAIN OUTCOME MEASURES: The General Health Questionnaire (12 item), the Nottingham Extended ADL Scale and the Nottingham Leisure Questionnaire, assessed by post, with telephone clarification. RESULTS: Four hundred and forty (94%) and 426 (91%) subjects were alive at 6 and 12 months, respectively. Three hundred and seventy-four (85% of survivors) and 311 (78% of survivors) responded at 6 and 12 month follow-up respectively. At six months and compared to the control group, those allocated to leisure therapy had nonsignificantly better GHQ scores (-1.2: 95% CI -2.9, +0.5), leisure scores (+0.7, 95% CI -1.1, +2.5) and Extended ADL scores (+0.4: 95% CI -3.8, +4.5): the ADL group had nonsignificantly better GHQ scores (-0.1: 95% CI -1.8, +1.7) and Extended ADL scores (+1.4: 95% CI -2.9, +5.6) and nonsignificantly worse leisure scores (-0.3: 95% CI -2.1, +1.6). The results at 12 months were similar. CONCLUSION: In contrast to the findings of previous smaller trials, neither of the additional OT treatments showed a clear beneficial effect on mood, leisure activity or independence in ADL measured at 6 or 12 months.


Subject(s)
Leisure Activities , Occupational Therapy , Stroke Rehabilitation , Activities of Daily Living , Affect , Aged , Female , Humans , Male , Quality of Life , Treatment Outcome
10.
Clin Rehabil ; 15(6): 647-56, 2001 Dec.
Article in English | MEDLINE | ID: mdl-11777095

ABSTRACT

OBJECTIVES: To reduce the length of the Nottingham Leisure Questionnaire (NLQ) in order to make it more suitable for postal use, and to evaluate its test-retest reliability, sensitivity, stability and validity in relation to other measures of activities of daily living (ADL), mood and handicap. METHOD: The NLQ was shortened and the response categories collapsed. Results from a previous trial which had used the NLQ were reanalysed to establish if significant group differences were maintained. The new version of the NLQ was subsequently tested for test-retest reliability on a new group of patients from the Nottingham stroke register who were asked to complete it twice. The new NLQ and other measures were sent to patients in a multicentre rehabilitation trial (TOTAL) six and twelve months after recruitment for postal completion. SUBJECTS: One hundred and thirty-seven consecutive patients from the Nottingham stroke register and 466 patients with a stroke in a multicentre rehabilitation trial. RESULTS: The original NLQ was reduced from 37 to 30 items and from five to three response categories. Data from an earlier study were reanalysed and differences between treatment groups remained. The results of a test-retest analysis using kappa showed that six items had excellent agreement, 15 good and nine fair, suggesting acceptable test-retest reliability. Results from the rehabilitation trial showed that the subjects performed all items and few additional activities were suggested. Higher NLQ scores were associated with higher subscores on the Nottingham Extended Activities of Daily Living Scale (NEADL) and lower NLQ scores with living alone and worse emotional health. CONCLUSION: The NLQ has been successfully modified for postal self-administration but there is potential for further development.


Subject(s)
Activities of Daily Living , Leisure Activities , Stroke Rehabilitation , Surveys and Questionnaires , England , Female , Humans , Male , Psychometrics , Regression Analysis , Reproducibility of Results
11.
J Sci Med Sport ; 3(1): 79-83, 2000 Mar.
Article in English | MEDLINE | ID: mdl-10839231

ABSTRACT

Six healthy, recreationally active, males undertook two weeks supplementation with beta-Hydroxy beta-Methylbutyrate (HMB). Supplementation was in capsule form with 3 g consumed each day in three even doses of 1 g at main meals. Mid stream urine samples were collected prior to, as well as, after one and two weeks of supplementation and subsequently analysed for testosterone and epitestosterone. The testosterone: epitestosterone ratio was not affected by 2 weeks of HMB supplementation (mean +/- SD baseline 1.02 +/- 0.68; week one 0.98 +/- 0.61; week two 0.92 +/- 0.62). Our results support the claim that supplementation with HMB at the doses recommended will not influence the urinary testosterone: epitestosterone ratio and thus not breach doping policies of the International Olympic Committee for exogenous testosterone or precursor administration.


Subject(s)
Doping in Sports , Epitestosterone/urine , Testosterone/urine , Valerates/administration & dosage , Adult , Dietary Supplements , Humans , International Agencies , Male
12.
Sports Med ; 28(6): 413-27, 1999 Dec.
Article in English | MEDLINE | ID: mdl-10623984

ABSTRACT

Concurrent strength and endurance training appears to inhibit strength development when compared with strength training alone. Our understanding of the nature of this inhibition and the mechanisms responsible for it is limited at present. This is due to the difficulties associated with comparing results of studies which differ markedly in a number of design factors, including the mode, frequency, duration and intensity of training, training history of participants, scheduling of training sessions and dependent variable selection. Despite these difficulties, both chronic and acute hypotheses have been proposed to explain the phenomenon of strength inhibition during concurrent training. The chronic hypothesis contends that skeletal muscle cannot adapt metabolically or morphologically to both strength and endurance training simultaneously. This is because many adaptations at the muscle level observed in response to strength training are different from those observed after endurance training. The observation that changes in muscle fibre type and size after concurrent training are different from those observed after strength training provide some support for the chronic hypothesis. The acute hypothesis contends that residual fatigue from the endurance component of concurrent training compromises the ability to develop tension during the strength element of concurrent training. It is proposed that repeated acute reductions in the quality of strength training sessions then lead to a reduction in strength development over time. Peripheral fatigue factors such as muscle damage and glycogen depletion have been implicated as possible fatigue mechanisms associated with the acute hypothesis. Further systematic research is necessary to quantify the inhibitory effects of concurrent training on strength development and to identify different training approaches that may overcome any negative effects of concurrent training.


Subject(s)
Muscle, Skeletal/physiology , Physical Endurance/physiology , Adaptation, Physiological , Glycogen/metabolism , Humans , Hypertrophy , Muscle Fibers, Skeletal/pathology , Recruitment, Neurophysiological
13.
Eur J Appl Physiol Occup Physiol ; 78(3): 270-5, 1998 Aug.
Article in English | MEDLINE | ID: mdl-9721008

ABSTRACT

Seventeen subjects performed resistance training of the leg extensor and flexor muscle groups two (2/wk) or three (3/wk) times per week. Changes in the relative myosin heavy chain (MHC) isoform contents (I, IIa and IIx) of the vastus lateralis and isometric, isokinetic and squat-lift one-repetition maximum (1 RM) strength were compared between conditions after both a common training period (6 weeks) and number of training sessions (18). After 6 weeks and 18 sessions (9 weeks for the 2/wk group), increments in 1RM strength for the 3/wk and 2/wk groups were similar [effect size (ES) differences approximately 0.3, 3/wk > 2/wk], whereas the 2/wk group presented greater isokinetic (ES differences = 0.3-1.2) and isometric (ES differences approximately 0.7) strength increases than the 3/wk condition. A significant (P < 0.05) increase in MHC IIa percentage was evident for the 2/wk group after 18 sessions. Both training groups exhibited a trend towards a reduction in the relative MHC IIx and an increase in MHC IIa contents (ES range = 0.5-1.24). However, correlations between changes in the strength and MHC profiles were weak (r2: 0.0-0.5). Thus, isometric and isokinetic strength responses to variations in training frequency differed from 1RM strength responses, and changes in strength were not strongly related to alterations in relative MHC content.


Subject(s)
Muscle, Skeletal/metabolism , Muscle, Skeletal/physiology , Myosin Heavy Chains/metabolism , Physical Fitness/physiology , Weight Lifting/physiology , Adolescent , Adult , Exercise , Female , Humans , Male
14.
Clin Rehabil ; 11(2): 107-13, 1997 May.
Article in English | MEDLINE | ID: mdl-9199862

ABSTRACT

OBJECTIVE: To determine whether stroke patients referred to the Social Service occupational therapy service would benefit from an enhanced service compared to the usual service. DESIGN: Randomized controlled study allocating patients to the enhanced service or the usual service. SUBJECTS: Stroke patients discharged home from hospital and referred to Social Service occupational therapy department. OUTCOME MEASURES: The sections and total score from the Nottingham Extended Activities of Daily Living Scale (EADL), the Barthel Index, the General Health Questionnaire (GHQ) and the number of pieces of equipment provided were analysed. RESULTS: One hundred and eleven stroke patients were recruited to this study. Fifty-three were randomly allocated to the enhanced service and 58 to the usual service. Patients receiving the enhanced service were seen more quickly after referral, for longer, and received significantly more visits (p < 0.01) than those receiving the usual service. Three months after entry to the study the enhanced service group had better EADL (p < 0.01) than the usual service group. This benefit remained significant in only the mobility section of the EADL at six months. Careers of the stroke patients in the enhanced group had lower GHQ scores (p < 0.05) than those in the usual group at six months. CONCLUSIONS: This trial supports the use of domiciliary occupational therapy for stroke patients after discharge from hospital in terms of improvements in functional outcomes in the short term, but the long-term benefits remain unclear.


Subject(s)
Cerebrovascular Disorders/rehabilitation , Occupational Therapy/methods , Social Work , Activities of Daily Living , Adaptation, Psychological , Aged , England , Female , Health Status , Humans , Male , Program Evaluation , Statistics, Nonparametric
15.
Sports Med ; 17(1): 22-38, 1994 Jan.
Article in English | MEDLINE | ID: mdl-8153497

ABSTRACT

Skeletal muscle tissue is sensitive to the acute and chronic stresses associated with resistance training. These responses are influenced by the structure of resistance activity (i.e. frequency, load and recovery) as well as the training history of the individuals involved. There are histochemical and biochemical data which suggest that resistance training alters the expression of myosin heavy chains (MHCs). Specifically, chronic exposure to bodybuilding and power lifting type activity produces shifts towards the MHC I and IIb isoforms, respectively. However, it is not yet clear which training parameters trigger these differential expressions of MHC isoforms. Interestingly, many programmes undertaken by athletes appear to cause a shift towards the MHC I isoform. Increments in the cross-sectional area of muscle after resistance training can be primarily attributed to fibre hypertrophy. However, there may be an upper limit to this hypertrophy. Furthermore, significant fibre hypertrophy appears to follow the sequence of fast twitch fibre hypertrophy preceding slow twitch fibre hypertrophy. Whilst some indirect measures of fibre number in living humans suggest that there is no interindividual variation, postmortem evidence suggests that there is. There are also animal data arising from investigations using resistance training protocols which suggest that chronic exercise can increase fibre number. Furthermore, satellite cell activity has been linked to myotube formation in the human. However, other animal models (i.e. compensatory hypertrophy) do not support the notion of fibre hyperplasia. Even if hyperplasia does occur, its effect on the cross-sectional area of muscle appears to be small. Phosphagen and glycogen metabolism, whilst important during resistance activity appear not to normally limit the performance of resistance activity. Phosphagen and related enzyme adaptations are affected by the type, structure and duration of resistance training. Whilst endogenous glycogen reserves may be increased with prolonged training, typical isotonic training for less than 6 months does not seem to increase glycolytic enzyme activity. Lipid metabolism may be of some significance in bodybuilding type activity. Thus, not surprisingly, oxidative enzyme adaptations appear to be affected by the structure and perhaps the modality of resistance training. The dilution of mitochondrial volume and endogenous lipid densities appears mainly because of fibre hypertrophy.


Subject(s)
Exercise/physiology , Muscles/physiology , Weight Lifting/physiology , Glycogen/metabolism , Humans , Hypertrophy , Lipid Metabolism , Muscles/pathology , Myosins/physiology , Phosphocreatine/metabolism
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