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1.
Clin Nutr ESPEN ; 46: 394-404, 2021 12.
Article in English | MEDLINE | ID: mdl-34857226

ABSTRACT

BACKGROUND & AIMS: The skeletal muscle anabolic effects of n-3 polyunsaturated fatty acids (n-3 PUFA) appear favoured towards women; a property that could be exploited in older women who typically exhibit poor muscle growth responses to resistance exercise training (RET). Here we sought to generate novel insights into the efficacy and mechanisms of n-3 PUFA alongside short-term RET in older women. METHODS: We recruited 16 healthy older women (Placebo n = 8 (PLA): 67±1y, n-3 PUFA n = 8: 64±1y) to a randomised double-blind placebo-controlled trial (n-3 PUFA; 3680 mg/day versus PLA) of 6 weeks fully-supervised progressive unilateral RET (i.e. 6 × 8 reps, 75% 1-RM, 3/wk-1). Strength was assessed by knee extensor 1-RM and isokinetic dynamometry âˆ¼ every 10 d. Thigh fat free mass (TFFM) was measured by DXA at 0/3/6 weeks. Bilateral vastus lateralis (VL) biopsies at 0/2/4/6 weeks with deuterium oxide (D2O) dosing were used to determine MPS responses for 0-2 and 4-6 weeks. Further, fibre cross sectional area (CSA), myonuclei number and satellite cell (SC) number were assessed, alongside muscle anabolic/catabolic signalling via immunoblotting. RESULTS: RET increased 1-RM equally in the trained leg of both groups (+23 ± 5% n-3 PUFA vs. +25 ± 5% PLA (both P < 0.01)) with no significant increase in maximum voluntary contraction (MVC) (+10 ± 6% n-3 PUFA vs. +13 ± 5% PLA). Only the n-3 PUFA group increased TFFM (3774 ± 158 g to 3961 ± 151 g n-3 PUFA (P < 0.05) vs. 3406 ± 201 g to 3561 ± 170 PLA) and type II fibre CSA (3097 ± 339 µm2 to 4329 ± 264 µm2 n-3 PUFA (P < 0.05) vs. 2520 ± 316 µm2 to 3467 ± 303 µm2 in PL) with RET. Myonuclei number increased equally in n-3 PUFA and PLA in both type I and type II fibres, with no change in SC number. N-3 PUFA had no added benefit on muscle protein synthesis (MPS), however, during weeks 4-6 of RET, absolute synthesis rates (ASR) displayed a trend to increase with n-3 PUFA only (5.6 ± 0.3 g d-1 to 7.1 ± 0.5 g d-1 n-3 PUFA (P = 0.09) vs. 5.5 ± 0.5 g d-1 to 6.5 ± 0.5 g d-1 PLA). Further, the n-3 PUFA group displayed greater 4EBP1 activation after acute RE at 6 weeks. CONCLUSION: n3-PUFA enhanced RET gains in muscle mass through type II fibre hypertrophy, with data suggesting a role for MPS rather than via SC recruitment. As such, the present study adds to a literature base illustrating the apparent enhancement of muscle hypertrophy with RET in older women fed adjuvant n3-PUFA.


Subject(s)
Resistance Training , Aged , Dietary Supplements , Exercise , Female , Humans , Middle Aged , Muscle Proteins , Muscle, Skeletal
2.
Prostate Cancer Prostatic Dis ; 23(4): 696-704, 2020 12.
Article in English | MEDLINE | ID: mdl-32157250

ABSTRACT

OBJECTIVES: To assess the efficacy of high-intensity interval training (HIIT) for improving cardiorespiratory fitness (CRF) in patients awaiting resection for urological malignancy within four weeks. SUBJECTS/PATIENTS AND METHODS: A randomised control trial of consecutive patients aged (>65 years) scheduled for major urological surgery in a large secondary referral centre in a UK hospital. The primary outcome is change in anaerobic threshold (VO2AT) following HIIT vs. standard care. RESULTS: Forty patients were recruited (mean age 72 years, male (39): female (1)) with 34 completing the protocol. Intention to treat analysis showed significant improvements in anaerobic threshold (VO2AT; mean difference (MD) 2.26 ml/kg/min (95% CI 1.25-3.26)) following HIIT. Blood pressure (BP) also significantly reduced in following: HIIT (SBP: -8.2 mmHg (95% CI -16.09 to -0.29) and DBP: -6.47 mmHg (95% CI -12.56 to -0.38)). No reportable adverse safety events occurred during HIIT and all participants achieved >85% predicted maximum heart rate during sessions, with protocol adherence of 84%. CONCLUSIONS: HIIT can improve CRF and cardiovascular health, representing clinically meaningful and achievable pre-operative improvements. Larger randomised trials are required to investigate the efficacy of prehabilitation HIIT upon different cancer types, post-operative complications, socio-economic impact and long-term survival.


Subject(s)
Cardiorespiratory Fitness/physiology , High-Intensity Interval Training/methods , Kidney Neoplasms/surgery , Preoperative Exercise/physiology , Prostatic Neoplasms/surgery , Urinary Bladder Neoplasms/surgery , Aged , Exercise , Female , Humans , Kidney Neoplasms/pathology , Male , Patient Acceptance of Health Care/statistics & numerical data , Patient Safety , Prostatic Neoplasms/pathology , Urinary Bladder Neoplasms/pathology
3.
Clin Nutr ; 38(5): 2071-2078, 2019 10.
Article in English | MEDLINE | ID: mdl-30360984

ABSTRACT

Age-related sarcopenia and dynapenia are associated with frailty and metabolic diseases. Resistance exercise training (RET) adjuvant to evidence-based nutritional intervention(s) have been shown as mitigating strategies. Given that ß-hydroxy-ß-methyl-butyrate (HMB) supplementation during RET improves lean body mass in younger humans, and that we have shown that HMB acutely stimulates muscle protein synthesis (MPS) and inhibits breakdown; we hypothesized that chronic supplementation of HMB free acid (HMB-FA) would enhance MPS and muscle mass/function in response to RET in older people. We recruited 16 healthy older men (Placebo (PLA): 68.5 ± 1.0 y, HMB-FA: 67.8 ± 1.15 y) for a randomised double-blind-placebo controlled trial (HMB-FA 3 × 1 g/day vs. PLA) involving a 6-week unilateral progressive RET regime (6 × 8 repetitions, 75% 1-RM, 3 · wk-1). Deuterium oxide (D2O) dosing was performed over the first two weeks (0-2 wk) and last two weeks (4-6 wk) with bilateral vastus lateralis (VL) biopsies at 0-2 and 4-6 wk (each time 75 ± 2 min after a single bout of resistance exercise (RE)) for quantification of early and later MPS responses and post-RE myogenic gene expression. Thigh lean mass (TLM) was measured by DXA, VL thickness and architecture (fibre length and pennation angle) by ultrasound at 0/3/6 wk, and strength by knee extensor 1-RM testing and MVC by isokinetic dynamometry (approx. every 10 days). RET induced strength increases (1-RM) in the exercised leg of both groups (398 ± 22N to 499 ± 30N HMB-FA vs. 396 ± 29N to 510 ± 43N PLA (both P < 0.05)). In addition, maximal voluntary contraction (MVC) also increased (179 ± 12 Nm to 203 ± 12 Nm HMB-FA vs. 185 ± 10 Nm to 217 ± 11 Nm PLA (both P < 0.05); with no group differences. VL muscle thickness increased significantly in the exercised leg in both groups, with no group differences. TLM (by DXA) rose to significance only in the HMB-FA group (by 5.8%-5734 ± 245 g p = 0.015 vs. 3.0% to 5644 ± 323 g P = 0.06 in PLA). MPS remained unchanged in the untrained legs (UT) 0-2 weeks being 1.06 ± 0.08%.d-1 (HMB-FA) and 1.14 ± 0.09%.d-1 (PLA), the trained legs (T) exhibited increased MPS in the HMB-FA group only at 0-2-weeks (1.39 ± 0.10%.d-1, P < 0.05) compared with UT: but was not different at 4-6-weeks: 1.26 ± 0.05%.d-1. However, there were no significant differences in MPS between the HMB-FA and PLA groups at any given time point and no significant treatment interaction observed. We also observed significant inductions of c-Myc gene expression following each acute RE bout, with no group differences. Further, there were no changes in any other muscle atrophy/hypertrophy or myogenic transcription factor genes we measured. RET with adjuvant HMB-FA supplements in free-living healthy older men did not enhance muscle strength or mass greater than that of RET alone (PLA). That said, only HMB-FA increased TLM, supported by early increases in chronic MPS. As such, chronic HMB-FA supplementation may result in long term benefits in older males, however longer and larger studies may be needed to fully determine the potential effects of HMB-FA supplementation; translating to any functional benefit.


Subject(s)
Muscle Strength/drug effects , Muscle, Skeletal/drug effects , Resistance Training , Valerates , Dietary Supplements , Double-Blind Method , Gene Expression/drug effects , Gene Expression/genetics , Humans , Male , Middle Aged , Muscle Development/drug effects , Muscle Development/genetics , Protein Biosynthesis/drug effects , Valerates/administration & dosage , Valerates/blood , Valerates/pharmacology
4.
Tech Coloproctol ; 20(6): 375-382, 2016 Jun.
Article in English | MEDLINE | ID: mdl-27015678

ABSTRACT

BACKGROUND: Over 41,000 people were diagnosed with colorectal cancer (CRC) in the UK in 2011. The incidence of CRC increases with age. Many elderly patients undergo surgery for CRC, the only curative treatment. Such patients are exposed to risks, which increase with age and reduced physical fitness. Endurance-based exercise training programmes can improve physical fitness, but such programmes do not comply with the UK, National Cancer Action Team 31-day time-to-treatment target. High-intensity interval training (HIT) can improve physical performance within 2-4 weeks, but few studies have shown HIT to be effective in elderly individuals, and those who do employ programmes longer than 31 days. Therefore, we investigated whether HIT could improve cardiorespiratory fitness in elderly volunteers, age-matched to a CRC population, within 31 days. METHODS: This observational cohort study recruited 21 healthy elderly participants (8 male and 13 female; age 67 years (range 62-73 years)) who undertook cardiopulmonary exercise testing before and after completing 12 sessions of HIT within a 31-day period. RESULTS: Peak oxygen consumption (VO2 peak) (23.9 ± 4.7 vs. 26.2 ± 5.4 ml/kg/min, p = 0.0014) and oxygen consumption at anaerobic threshold (17.86 ± 4.45 vs. 20.21 ± 4.11 ml/kg/min, p = 0.008) increased after HIT. CONCLUSIONS: It is possible to improve cardiorespiratory fitness in 31 days in individuals of comparable age to those presenting for CRC surgery.


Subject(s)
Exercise Test/methods , Exercise Therapy/methods , Exercise Tolerance , High-Intensity Interval Training/methods , Aged , Anaerobic Threshold , Cohort Studies , Female , Healthy Volunteers , Humans , Male , Middle Aged , Oxygen Consumption , Physical Fitness , Time-to-Treatment , Treatment Outcome
5.
Tech Coloproctol ; 20(2): 81-9, 2016 Feb.
Article in English | MEDLINE | ID: mdl-26614304

ABSTRACT

The aim of this systematic review was to evaluate the evidence for exercise interventions prior to surgery for colorectal cancer resection. The evidence for use of exercise to improve physical fitness and surgical outcomes is as yet unknown. A systematic search was performed of MEDLINE, EMBASE, CINAHL, AMED and BNI databases for studies involving pre-operative exercise in colorectal cancer patients. Eight studies were included in the review. There is evidence that pre-operative exercise improves functional fitness, and to a lesser extent objectively measurable cardio-respiratory fitness prior to colorectal cancer resection. There is no clear evidence at present that this improvement in fitness translates into reduced peri-operative risk or improved post-operative outcomes. Current studies are limited by risk of bias. This review highlights the common difficulty in transferring promising results in a research setting, into significant improvements in the clinical arena. Future research should focus on which type of exercise is most likely to maximise patient adherence and improvements in cardio-respiratory fitness. Ultimately, adequately powered, randomised controlled trials are needed to investigate whether pre-operative exercise improves post-operative morbidity and mortality.


Subject(s)
Colectomy , Colorectal Neoplasms/surgery , Exercise Therapy/methods , Physical Fitness , Preoperative Care/methods , Humans
6.
Tech Coloproctol ; 19(6): 347-54, 2015 Jun.
Article in English | MEDLINE | ID: mdl-25972298

ABSTRACT

BACKGROUND: There is no consensus amongst colorectal surgeons as to whether preoperative exercise is beneficial in the management of colorectal cancer patients. Research has shown higher rates of postoperative complications in patients who are less fit. Agreement needs to be sought on whether improving fitness via exercise should be a part of preoperative care. The Delphi process is an iterative process designed to refine opinions on a subject, until consensus agreement is reached within an expert group. METHODS: We performed a Delphi survey with a group of consultant colorectal surgeons. Statements achieving >80% agreement were taken as consensus, those achieving >80% disagreement were removed, and those in between were revised in the following round. The process ended with a group of statements which achieved consensus. RESULTS: Thirty-two statements were included in the first round of the survey. After three rounds of the survey, 21 statements were accepted as consensus, six statements were rejected, and seven statements did not reach consensus. It was agreed that exercise training should form part of preoperative care and would be supported by surgeons. That suitable programmes pose significant risk to patients was rejected. There was no consensus reached on the strength of current available evidence or whether it would be possible to deliver exercise programmes. CONCLUSIONS: This work is the first to produce a set of statements on which expert consensus opinion has been agreed regarding preoperative exercise in colorectal cancer patients. Future work, informed by this study, will design interventions to produce rapid improvements in fitness before surgery.


Subject(s)
Colorectal Neoplasms/therapy , Consensus , Delphi Technique , Exercise Therapy/standards , Physical Fitness , Aged , Exercise Therapy/methods , Humans
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