1
|
Effects of high-intensity interval training combined with traditional strength or power training on functionality and physical fitness in healthy older men: A randomized controlled trial. Exp Gerontol 2021; 149:111321. [PMID: 33757813 DOI: 10.1016/j.exger.2021.111321] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2021] [Revised: 02/24/2021] [Accepted: 03/16/2021] [Indexed: 11/18/2022]
Abstract
Concurrent training (CT) is an efficient strategy to improve neuromuscular function and cardiorespiratory fitness in older adults, which are factors of pivotal importance for the maintenance of functional capacity with aging. However, there is a lack of evidence about the effectiveness of power training (PT) as an alternative to traditional strength training (TST) during CT. Thus, the aim of the present study was to examine the effect of 16 weeks (twice weekly) TST combined with high intensity interval training (TST + HIIT) vs. PT combined with HIIT (PT + HIIT) on functional performance, cardiorespiratory fitness and body composition in older men. Thirty five older men (65.8 ± 3.9 years) were randomly allocated into two training groups: TST + HIIT (n = 18), and PT + HIIT (n = 17). TST + HIIT performed resistance training at intensities ranging from 65% to 80% 1RM at slow controlled speed (≅ 2 s for each concentric phase), whereas PT + HIIT trained at intensities ranging from 40% to 60% of 1RM at maximal intentional speed. Both groups performed HIIT at intensities ranging from 75 to 90% of VO2peak. Participants performed functional tests (sit-to-stand, timed-up-and-go, stair climbing); cardiopulmonary exercise testing (maximal cycling power output: Wmax, peak oxygen uptake: VO2peak, cycling economy), as well as body composition assessment (DXA) before, post 8 and post 16 weeks of training. The groups improved similarly (P < 0.05) with training in all functional capacity outcomes, Wmax, cycling economy, VO2peak and body composition (P < 0.05). These findings suggest that HIIT based CT programs involving TST vs. PT are equally effective in improving functionality, cardiorespiratory fitness and body composition in healthy older men.
Collapse
|
2
|
Correction: Effect of exercise intensity on postprandial lipemia, markers of oxidative stress, and endothelial function after a high-fat meal. Appl Physiol Nutr Metab 2020; 45:1400. [PMID: 33151758 DOI: 10.1139/apnm-2020-0927] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
|
3
|
Predictive equations for evaluation for resting energy expenditure in Brazilian patients with type 2 diabetes: what can we use? BMC Nutr 2020; 6:56. [PMID: 33005431 PMCID: PMC7525981 DOI: 10.1186/s40795-020-00384-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2020] [Accepted: 09/20/2020] [Indexed: 11/18/2022] Open
Abstract
BACKGROUND Evaluation of the resting energy expenditure (REE) is essential to ensure an appropriate dietary prescription for patients with type 2 diabetes. The aim of this record was to evaluate the accuracy of predictive equations for REE estimation in patients with type 2 diabetes, considering indirect calorimetry (IC) as the reference method. METHODS A cross-sectional study was performed in outpatients with type 2 diabetes. Clinical, body composition by electrical bioimpedance and laboratory variables were evaluated. The REE was measured by IC (QUARK RMR, Cosmed, Rome, Italy) and estimated by eleven predictive equations. Data were analyzed using Bland-Altman plots, paired t-tests, and Pearson's correlation coefficients. RESULTS Sixty-two patients were evaluated [50% female; mean age 63.1 ± 5.2 years; diabetes duration of 11 (1-36) years, and mean A1C of 7.6 ± 1.2%]. There was a wide variation in the accuracy of REE values predicted by equations when compared to IC REE measurement. In all patients, Ikeda and Mifflin St-Jeor equations were that most underestimated REE. And, the equations that overestimated the REE were proposed by Dietary Reference Intakes and Huang. The most accurate equations were FAO/WHO/UNO in women (- 1.8% difference) and Oxford in men (- 1.3% difference). CONCLUSION In patients with type 2 diabetes, in the absence of IC, FAO/WHO/UNO and Oxford equations provide the best REE prediction in comparison to measured REE for women and men, respectively.
Collapse
|
4
|
Effects of Traditional and Vascular Restricted Strength Training Program With Equalized Volume on Isometric and Dynamic Strength, Muscle Thickness, Electromyographic Activity, and Endothelial Function Adaptations in Young Adults. J Strength Cond Res 2020; 34:689-698. [PMID: 30063556 DOI: 10.1519/jsc.0000000000002717] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Ramis, TR, Muller, CHdL, Boeno, FP, Teixeira, BC, Rech, A, Pompermayer, MG, Medeiros, NdS, Oliveira, ÁRd, Pinto, RS, and Ribeiro, JL. Effects of traditional and vascular restricted strength training program with equalized volume on isometric and dynamic strength, muscle thickness, electromyographic activity, and endothelial function adaptations in young adults. J Strength Cond Res 34(3): 689-698, 2020-The purpose of the study was to evaluate and compare the acute and chronic effects of partial vascular occlusion training in young, physically active adults. Neuromuscular, morphological, and endothelial function responses were compared between high-intensity resistance training (HI-RT) and low-intensity resistance training with partial vascular occlusion (LI-BFR), despite the same training volume. The 28 subjects (age, 23.96 ± 2.67 years) were randomly assigned into 2 groups: LI-BFR (n = 15) and HI-RT (n = 13). Both groups performed unilateral exercise of elbow flexion (EF) and knee extension (KE) 3 times per week for 8 weeks. This study was approved by the ethics committee. Flow-mediated dilation showed a significant difference in baseline and post-training in the LI-BFR group (4.44 ± 0.51 vs. 6.35 ± 2.08 mm, respectively). For nitrite/nitrate concentrations only, there was a significant difference when comparing pre- and post-acute exercise in both groups. The torque and rep. Sixty percent 1 repetition maximum had improvements in both groups. There were differences between groups only in isometric delta EF and isokinetic delta KE (EF 3.42 ± 5.09 and 9.61 ± 7.52 N·m; KE 12.78 ± 25.61 and 42.69 ± 35.68 N·m; LI-BFR and HI-RT groups, respectively). There was a significant increase of muscle thickness in both groups. An increase of both isokinetic and isometric electromyography (EMG) of biceps of the HI-RT group was observed. The same was observed for the LI-BFR group regarding isokinetic and isometric EMG of vastus lateralis. Thus, in addition to strength and hypertrophy gains, this study also shows benefits related to vascular function. For practical applications, this study demonstrates a clinical importance of LI-BFR training as an alternative methodology.
Collapse
|
5
|
Relationship between insulin resistance and adipocytokines: the mediator role of adiposity in children. Ann Hum Biol 2020; 47:244-249. [PMID: 32279531 DOI: 10.1080/03014460.2020.1740320] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Background: Leptin and adiponectin interact with each other in the modulation of obesity and insulin resistance (IR) and it is also important to consider the role of cardiorespiratory and muscular fitness in these relationships.Aim: To analyse the relationship between IR with adipocytokines in children, and to test the mediation effect of %BF (percentage of body fat) in the association of IR with leptin, adiponectin, and L/A ratio.Subjects and methods: This cross-sectional study comprised a sample of 150 schoolchildren, aged 6-11 years, from school in Porto Alegre, Brazil. The following variables were evaluated: cardiorespiratory fitness (CRF), muscular fitness (MF), percentage of body fat (%BF), and biochemical variables (leptin, adiponectin, glucose, and insulin).Results: IR was associated with leptin and L/A ratio, after adjustments for age, sex, sexual maturation, and CRF. When adjusted for age, sex, sexual maturation, and MF, an association was found between IR with leptin and L/A ratio. Moreover, %BF was a mediator in the association between IR and leptin, as well as IR and L/A ratio, explaining 54% and 57% of these associations, respectively.Conclusion: Leptin and L/A ratio are positively associated with IR after adjustments. Also, %BF is a mediator in the associations between IR and leptin and L/A ratio.
Collapse
|
6
|
Modulatory Effects of Acute Aerobic Moderate Exercise on Purinergic Enzymes in Sedentary and Physically Active Males. FASEB J 2020. [DOI: 10.1096/fasebj.2020.34.s1.09386] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
|
7
|
Acute glycemic responses along 10-week high-intensity training protocols in type 1 diabetes patients. Diabetes Res Clin Pract 2019; 153:111-113. [PMID: 31195026 DOI: 10.1016/j.diabres.2019.06.001] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/13/2019] [Revised: 05/08/2019] [Accepted: 06/03/2019] [Indexed: 10/26/2022]
Abstract
Glycemic fluctuations were compared throughout 10-week high-intensity training protocols in T1DM patients. Differences were compared using the rate of change in glycaemia during exercise (RoCE). HIIT sessions led to lower RoCE in most weeks than other training protocols. The occurrence of level 1 hypoglycemia along sessions were similar among interventions.
Collapse
|
8
|
Effects of a Single Session of High- and Moderate-Intensity Resistance Exercise on Endothelial Function of Middle-Aged Sedentary Men. Front Physiol 2019; 10:777. [PMID: 31293446 PMCID: PMC6598115 DOI: 10.3389/fphys.2019.00777] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2018] [Accepted: 06/04/2019] [Indexed: 01/30/2023] Open
Abstract
Regular resistance exercise is associated with metabolic, neuromuscular and cardiovascular adaptations which improve quality of life and health. However, sedentary subjects have shown acute impairments in endothelial function after high-intensity resistance exercise. The aim of this study was to evaluate endothelial function in sedentary middle-aged men after a single session of resistance exercise at different intensities. Eleven sedentary middle-aged men (40.1 ± 3.9 years; 27.3 ± 1.4 kg/m2) underwent three different conditions of assessment: (1) single knee extension exercise at moderate intensity (MI) [4 sets of 12 repetitions at 50% of one repetition maximum (1RM) for each leg], (2) single knee extension exercise at high intensity (HI) (4 sets of 8 repetitions at 80% of 1RM for each leg), (3) resting for the control condition (CON). Flow-mediated dilation (FMD) was assessed before, 30 and 60 min after exercise. Plasma concentrations of endothelin-1 (ET-1), nitrites and nitrates (NOx) and thiobarbituric acid reactive substances (TBARS) were measured before, immediately after and 60 min after exercise. Blood pressure (BP) was measured prior to the experimental protocols, and in the following times: immediately following, and 2, 5, 10, 15, 30, and 60 min after exertion. There was a significant improvement in FMD 30 min after MI condition (12.5 ± 4.10 vs. 17.2 ± 3.9%; p = 0.016). NOx levels were significantly higher immediately after MI (6.8 ± 3.3 vs. 12.6 ± 4.2 μM; p = 0.007) and there was a significant increase in the concentration of ET-1 immediately after HI (20.02 ± 2.2 vs. 25.4 ± 2.1 pg/mL; p = 0.004). However, there was no significant difference for BP (MI vs. HI) and TBARS among the experimental conditions. Resistance exercise performed at moderate intensity improved vasodilatation via increases on NOx levels and FMD in sedentary middle-aged men.
Collapse
|
9
|
Effects of dancing compared to walking on cardiovascular risk and functional capacity of older women: A randomized controlled trial. Exp Gerontol 2018; 114:67-77. [PMID: 30389581 DOI: 10.1016/j.exger.2018.10.015] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2018] [Revised: 10/18/2018] [Accepted: 10/20/2018] [Indexed: 10/28/2022]
Abstract
INTRODUCTION Aging is characterized by reductions in lean mass simultaneously to increases in visceral adipose tissue, elevating cardiovascular risk (CVR) and physical dependence. Dancing has been recommended for improving fall-risk and CVR, however, comparisons with traditional exercises are limited. This study aimed to compare the effects of dancing with walking on CVR and functionality of older women. METHODS Thirty sedentary women (65 ± 5 years, BMI 27 ± 4 kg/m2) were randomized into three groups (n = 10/group): dancing, walking or stretching (active control). All interventions lasted 8 weeks (60 min sessions): dancing/walking 3×/week, stretching 1×/week. Dancing: several styles, no partner. Walking: treadmill, 60% peak oxygen consumption (VO2peak). Stretching: large muscle groups, no discomfort. Before and after interventions assessments: VO2peak (primary outcome), total cholesterol, HDL-C, LDL-C, glucose, insulin, CRP, TNF-α, waist and hip circumferences, visceral adipose tissue (VAT), muscle thickness, maximal muscle strength/power, static and dynamic balance, gait ability, flexibility, chair-raise and level of physical activity (PA). STATISTICS generalized estimating equations, post-hoc LSD (p < 0.05), SPSS 22.0. RESULTS (Mean-CI): (before vs after): group vs time interaction showed increases in VO2peak (mL·kg-1·min-1) for dancing 23.3 (20.8-25.8) vs 25.6 (23.4-27.8), and walking 23.4 (21.3-25.5) vs 27.0 (25.4-28.6), with no differences for stretching 23.5 (21.3-25.7) vs 23.0 (21.0-24.9). Lower body muscle power and static balance also improved for dancing and walking, but not for stretching. Main time effect showed improvements in CRP, TNF-α, LDL-C, HDL-C, VAT, waist, hip, chair raise, flexibility and level of daily PA for all groups. CONCLUSION Dancing induced similar increases in VO2peak, lower body muscle power and static balance as walking, while the stretching group remained unchanged. Pooled effects showed improvements in body composition, lipid and inflammatory profile, which are supported by increased PA levels. TRIAL REGISTRATION NCT03262714.
Collapse
|
10
|
Functional and physiological adaptations following concurrent training using sets with and without concentric failure in elderly men: A randomized clinical trial. Exp Gerontol 2018; 110:182-190. [DOI: 10.1016/j.exger.2018.06.011] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2018] [Revised: 06/06/2018] [Accepted: 06/11/2018] [Indexed: 12/23/2022]
|
11
|
Acute and residual effects of aerobic exercise on fructose-induced postprandial lipemia on lean male subjects. Eur J Nutr 2018; 58:2293-2303. [DOI: 10.1007/s00394-018-1780-4] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2018] [Accepted: 07/15/2018] [Indexed: 12/19/2022]
|
12
|
Cardiorespiratory responses of a dance session designed for older women: A cross sectional study. Exp Gerontol 2018; 110:139-145. [PMID: 29879448 DOI: 10.1016/j.exger.2018.06.003] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2018] [Revised: 05/30/2018] [Accepted: 06/02/2018] [Indexed: 11/28/2022]
Abstract
BACKGROUND Dancing has been increasingly used as a type of exercise intervention to improve cardiovascular fitness of older people. However, it is unclear which may be the exercise intensity of the dance sessions. OBJECTIVE To describe cardiorespiratory responses of a dance session for older women, and to identify intensity zones in relation to peak oxygen consumption (VO2peak), first and second ventilatory thresholds (VT1 and VT2). METHODS Ten women (66 ± 5 yrs., BMI 27 ± 4) were examined on three occasions: Familiarization, maximum effort and dance sessions. Incremental treadmill test: 5 km/h, 2% slope each min, until maximum effort. Dance class (60 min): warm-up (20 min), across-the-floor (10 min), choreography (15 min), show (10 min) and cool-down (5 min). Ventilatory parameters were measured continuously (breath-by-breath). RESULTS VO2 (mL·kg-1·min-1): Maximum effort: VO2peak (23.3 ± 4.3), VT1 (17.2 ± 3.5) and VT2 (20.9 ± 3.4). Dancing: warm-up (12.8 ± 2.4, ~55%VO2peak), across-the-floor (14.2 ± 2.4 ~62%VO2peak), choreography (14.6 ± 3.2 ~63%VO2peak) and show (16.1 ± 3.3, ~69% VO2peak). Show was similar to VT1. CONCLUSIONS Cardiorespiratory demands of a dance class for older women are at low aerobic intensity. Show was similar to VT1, indicating that a dance class may be modulated to improve aerobic fitness, at least at initial stages of training.
Collapse
|
13
|
Acute effects of strength exercise with blood flow restriction on vascular function of young healthy males. J Vasc Bras 2018; 17:122-127. [PMID: 30377421 PMCID: PMC6205709 DOI: 10.1590/1677-5449.011017] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023] Open
Abstract
Background Strength training with blood flow restriction (STBFR) provokes similar neuromuscular adaptations to traditional strength training using low training loads. However, there is a need for better understanding of the repercussions for antioxidant parameters and vascular function. Objectives: The objective of the present study was to investigate the effects of a session of low intensity strength training with blood flow restriction, compared with high intensity and low intensity strength training without blood flow restriction, on the levels of nitric oxide products and antioxidant enzyme activity in healthy young men. Methods: Eleven young men performed three strength exercise sessions: low intensity with blood flow restriction (LIBFR), high intensity (HI), and low intensity (LI). Activity of the antioxidant enzymes catalase (CAT) and superoxide dismutase (SOD) was assessed and metabolites of nitric oxide (NOx) were assayed before and after each session. Results: There were no changes to NOx plasma levels under the different exercise conditions (p > 0.05). However, SOD activity exhibited a significant reduction after the LIBFR condition (p < 0.05), while CAT activity reduced significantly after the LI condition (p < 0.05). Conclusions: The results of this study suggest that one session of low intensity strength training with blood flow restriction does not reduce bioavailability of nitric oxide or induce redox imbalance in healthy young men.
Collapse
|
14
|
Ingestion of carbohydrate or carbohydrate plus protein does not enhance performance during endurance exercise: a randomized crossover placebo-controlled clinical trial. Appl Physiol Nutr Metab 2018; 43:937-944. [PMID: 29544062 DOI: 10.1139/apnm-2017-0835] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
A beverage containing protein (PRO) and carbohydrate (CHO) may have an ergogenic effect on endurance performance. However, evidence regarding its efficacy on similar conditions to athletes' race day is still lacking. The objective of this study was to compare the effects of 3 different nutritional supplementation strategies on performance and muscle recovery in a duathlon protocol. Thirteen male athletes (29.7 ± 7.7 years) participated in 3 simulated Olympic-distance duathlon trials (SDTs) under 3 different, randomly assigned supplementation regimens: CHO drink (75 g CHO), isocaloric CHO plus PRO drink (60.5 g CHO and 14.5 g PRO), and placebo drink (PLA). Supplements were offered during the cycling bout. Blood samples were collected before, immediately after, and 24 h after each SDT for creatine kinase (CK) analysis. Isometric peak torque (PT) was measured before and 24 h after each SDT. The primary outcome measure was the time to complete the 5-km running section (t5km) at a self-selected pace. There was no difference in t5km between CHO (1270.3 ± 130.5 s), CHO+PRO (1267.2 ± 138.9 s), and PLA (1275.4 ± 120 s); p = 0.87, effect size (ES) ≤ 0.1. Pre-post changes for PT and CK were not significant for any of the 3 conditions (PT: p = 0.24, ES ≤ 0.4; CK: p = 0.32, ES = 0.3-1.04). For endurance sports lasting up to 2 h, with a pre-exercise meal containing CHO at 1.5 g·kg-1, supplementation with CHO or CHO+PRO does not offer additional benefits for performance and muscle recovery when compared with PLA.
Collapse
|
15
|
Hypotensive Response to Continuous Aerobic and High-Intensity Interval Exercise
Matched by Volume in Sedentary Subjects. INTERNATIONAL JOURNAL OF CARDIOVASCULAR SCIENCES 2018. [DOI: 10.5935/2359-4802.20180084] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
|
16
|
Effect of exercise intensity on postprandial lipemia, markers of oxidative stress, and endothelial function after a high-fat meal. Appl Physiol Nutr Metab 2016; 41:1278-1284. [PMID: 27841024 DOI: 10.1139/apnm-2016-0262] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
The aim of this study was to compare the effects of 2 different exercise intensities on postprandial lipemia, oxidative stress markers, and endothelial function after a high-fat meal (HFM). Eleven young men completed 2-day trials in 3 conditions: rest, moderate-intensity exercise (MI-Exercise) and heavy-intensity exercise (HI-Exercise). Subjects performed an exercise bout or no exercise (Rest) on the evening of day 1. On the morning of day 2, an HFM was provided. Blood was sampled at fasting (0 h) and every hour from 1 to 5 h during the postprandial period for triacylglycerol (TAG), thiobarbituric acid reactive substance (TBARS), and nitrite/nitrate (NOx) concentrations. Flow-mediated dilatation (FMD) was also analyzed. TAG concentrations were reduced in exercise conditions compared with Rest during the postprandial period (P < 0.004). TAG incremental area under the curve (iAUC) was smaller after HI-Exercise compared with Rest (P = 0.012). TBARS concentrations were reduced in MI-Exercise compared with Rest (P < 0.041). FMD was higher in exercise conditions than Rest at 0 h (P < 0.02) and NOx concentrations were enhanced in MI-Exercise compared with Rest at 0 h (P < 0.01). These results suggest that acute exercise can reduce lipemia after an HFM. However, HI-Exercise showed to be more effective in reducing iAUC TAG, which might suggest higher protection against postprandial TAG enhancement. Conversely, MI-Exercise can be beneficial to attenuate the susceptibility of oxidative damage induced by an HFM and to increase endothelial function in the fasted state compared with Rest.
Collapse
|
17
|
Oxygen desaturation during the six-minute walk test in COPD patients. J Bras Pneumol 2015; 40:222-8. [PMID: 25029644 PMCID: PMC4109193 DOI: 10.1590/s1806-37132014000300004] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2013] [Accepted: 04/05/2014] [Indexed: 11/21/2022] Open
Abstract
OBJECTIVE To evaluate the behavior of oxygen saturation curves throughout the six-minute walk test (6MWT) in patients with COPD. METHODS We included 85 patients, all of whom underwent spirometry and were classified as having moderate COPD (modCOPD, n = 30) or severe COPD (sevCOPD, n = 55). All of the patients performed a 6MWT, in a 27-m corridor with continuous SpO2 and HR monitoring by telemetry. We studied the SpO2 curves in order to determine the time to a 4% decrease in SpO2, the time to the minimum SpO2 (Tmin), and the post-6MWT time to return to the initial SpO2, the last designated recovery time (RT). For each of those curves, we calculated the slope. RESULTS The mean age in the modCOPD and sevCOPD groups was 66 ± 10 years and 62 ± 11 years, respectively. At baseline, SpO2 was > 94% in all of the patients; none received supplemental oxygen during the 6MWT; and none of the tests were interrupted. The six-minute walk distance did not differ significantly between the groups. The SpO2 values were lowest in the sevCOPD group. There was no difference between the groups regarding RT. In 71% and 63% of the sevCOPD and modCOPD group patients, respectively, a ≥ 4% decrease in SpO2 occurred within the first minute. We found that FEV1% correlated significantly with the ΔSpO2 (r = -0.398; p < 0.001), Tmin (r = -0.449; p < 0.001), and minimum SpO2 (r = 0.356; p < 0.005). CONCLUSIONS In the sevCOPD group, in comparison with the modCOPD group, SpO2 was lower and the Tmin was greater, suggesting a worse prognosis in the former.
Collapse
|