Aerobic exercise and resistance training for the management of type 2 diabetes mellitus

BACKGROUND
Implementation of a structured physical exercise program can improve glycemic control in patients with type 2 diabetes mellitus.

OBJECTIVE
To evaluate the efficacy of aerobic exercise and resistance training (either alone or in combination) in the management of type 2 diabetes mellitus.

DESIGN AND INTERVENTION
DARE (Diabetes Aerobic and Resistance Exercise) was a 26-week, single-center, parallel-group, randomized, controlled trial of patients with type 2 diabetes mellitus of >6 months' duration. Participants were aged 39-70 years with a baseline [HbA.sub.1c] level 6.6-9.9%. Exclusion criteria included current insulin therapy, regular exercise regime and blood pressure >160/95 mmHg. All participants underwent a 4-week run-in period that comprised 12 sessions of combined aerobic exercise and resistance training; participants who attended [greater than or equal to] 10 sessions were eligible to enter the study. Eligible participants were randomly allocated to one of four groups: aerobic exercise alone; resistance training alone; combined aerobic exercise and resistance training; and no intervention (control group). Exercise was performed three times weekly. The aerobic exercise group progressed from 15-20 min on a treadmill or bicycle ergometer per session at 60% of the maximum heart rate to 45 min per session at 75% of the maximum heart rate. The resistance training group performed 7 different exercises on weight machines per 45 min session, and progressed to 2-3 sets of each exercise at the maximum weight that could be lifted 7-9 times. The combined exercise group performed the full aerobic exercise program plus the full resistance training program. Participants in the control group reverted to their pre-study exercise levels.

OUTCOME MEASURES
The primary outcome measure was the change in [HbA.sub.1c] from baseline. Secondary outcome measures included changes in blood pressure, lipid profile, and body composition.

RESULTS
A total of 251 participants were eligible for intervention. The median session attendance was 80% (aerobic exercise), 85% (resistance training) and 86% (combined exercise). When compared with the control group, the HbA1c levels were reduced by 0.50% in the aerobic exercise group (P = 0.007) and by 0.38% in the resistance training group (P = 0.038). The combined exercise group had an additional reduction of 0.46% when compared with the aerobic exercise group (P = 0.014) and of 0.59% when compared with the resistance training group (P = 0.001). Decreases in [HbA.sub.1c] levels were greatest for participants with a baseline [HbA.sub.1c] level = 7.5% (P <0.001). For participants with a baseline level [HbA.sub.1c] <7.5%, significant improvements in glycemic control were observed in the combined exercise group only (P = 0.002). Changes in blood pressure and lipid profiles did not differ between the groups. By contrast, participation in a structured exercise program improved body composition.

CONCLUSION
Although aerobic exercise or resistance training alone improved glycemic control, additional improvements were observed with the combined exercise regimen.

Community center-based resistance training for the maintenance of glycemic control in adults with type 2 diabetes

OBJECTIVE--The purpose of this study Was to determine whether beneficial effects on glycemic control of an initial laboratory-supervised resistance training program could be sustained through a community center-based maintenance program.

RESEARCH DESIGN AND METHODS--We studied 57 overweight (BMI [greater than or equal to] 27 kg/[m.sup.2]) sedentary men and women aged 40-80 years with established (>6 months) type 2 diabetes. Initially, all participants attended a twice-weekly 2-month supervised resistance training program conducted in the exercise laboratory. Thereafter, participants undertook a resistance training maintenance program (2 times/week) for 12 months and were randomly assigned to carry this out either in a community fitness and recreation center (center) or in their domestic environment (home). Glycemic control ([HbA.sub.1c] [A1C]) was assessed at 0, 2, and 14 months.

RESULTS--Pooling data from the two groups for the 2-month supervised resistance training program showed that compared with baseline, mean A1C fell by -0.4% [95% CI -0.6 to -0.2]. Within-group comparisons showed that A1C remained lower than baseline values at 14 months in the center group (-0.4% [-0.7 to -0.03]) but not in the home group (-0.1% [-0.4 to 0.3]). However, no between-group differences were observed at each time point. Changes in A1C during the maintenance period were positively associated with exercise adherence in the center group only.

CONCLUSIONS--Center-based but not home-based resistance training was associated with the maintenance of modestly improved glycemic control from baseline, which was proportional to program adherence. Our findings emphasize the need to develop and test behavioral methods to promote healthy lifestyles including increased physical activity in adults with type 2 diabetes.

Effect of a low-resource-intensive lifestyle modification program incorporating gymnasium-based and home-based resistance training on type 2 diabetes risk in Australian adults

OBJECTIVE--The purpose of this study was to assess the effectiveness of a low-resource-intensive lifestyle modification program incorporating resistance training and to compare a gymnasium-based with a home-based resistance training program on diabetes diagnosis status and risk.

RESEARCH DESIGN AND METHODS--A quasi-experimental two-group study was undertaken with 122 participants with diabetes risk factors; 36.9% had impaired glucose tolerance (1GT) or impaired fasting glucose (IFG) at baseline. The intervention included a 6-week group self-management education program, a gymnasium-based or home-based 12-week resistance training program, and a 34-week maintenance program. Fasting plasma glucose (FPG) and 2-h plasma glucose, blood lipids, blood pressure, body composition, physical activity, and diet were assessed at baseline and week 52.

RESULTS--Mean 2-h plasma glucose and FPG fell by 0.34 mmol/1 (95% CI--0.60 to--0.08) and 0.15 mmol/l (-0.23 to -0.07), respectively. The proportion of participants with IFG or IGT decreased from 36.9 to 23.0% (P = 0.006). Mean weight loss was 4.07 kg (-4.99 to -3.15). The only significant difference between resistance training groups was a greater reduction in systolic blood pressure for the gymnasium-based group (P = 0.008).

CONCLUSIONS--This intervention significantly improved diabetes diagnostic status and reduced diabetes risk to a degree comparable to that of other low-resource-intensive lifestyle modification programs and more intensive interventions applied to individuals with IGT. The effects of home-based and gymnasium-based resistance training did not differ significantly.

Phylogenetic relationships among nine scallop species (Bivalvia : Pectinidae) inferred from nucleotide sequences of one mitochondrial and three nuclear gene regions

Current knowledge of the evolutionary relationships among scallop species (Mollusca: Bivalvia: Pectinidae) in the Indo-Pacific region is rather scanty. To enhance the understanding of the relationships within this group, phylogenies of nine species of scallops with the majority from coastal regions of Thailand, were reconstructed by maximum parsimony, maximum likelihood, and Bayesian methods using sequences of the 16S rRNA of the mitochondrial genome, and a fragment containing the ITS1, 5.8S and ITS2 genes of the nuclear DNA. The trees that resulted from the three methods of analysis were topologically identical, however, gained different levels of support at some nodes. Nine species were clustered into two major clades, corresponding to two subfamilies (Pectininae and Chlamydinae) of the three currently recognized subfamilies within Pectinidae. Overall, the relationships reported herein are mostly in accordance with the previous molecular studies that used sequences of the mtDNA cytochrome oxidase subunit I, and the classification system based on microsculpture of shell features and morphological characteristics of juveniles. Levels of divergences were different among genes (i.e., the 5.8S gene showed the lowest levels of nucleotide divergence at all levels, whereas the 16S rRNA showed the highest level of variation within species, and ITS2 gene revealed the highest level of divergence at higher levels).

Screening for type 2 diabetes and impaired glucose metabolism – the Australian experience

OBJECTIVE--To assess the Australian protocol for identifying undiagnosed type 2 diabetes and impaired glucose metabolism.

RESEARCH DESIGN AND METHODS--The Australian screening protocol recommends a stepped approach to detecting undiagnosed type 2 diabetes based on assessment of risk status, measurement of fasting plasma glucose (FPG) in individuals at risk, and further testing according to FPG. The performance of and variations to this protocol were assessed in a population-based sample of 10,508 Australians.

RESULTS--The protocol had a sensitivity of 79.9%, specificity of 79.9%, and a positive predictive value (PPV) of 13.7% for detecting undiagnosed type 2 diabetes and sensitivity of 51.9% and specificity of 86.7% for detecting impaired glucose tolerance (IGT) or impaired fasting glucose (IFG). To achieve these diagnostic rates, 20.7% of the Australian adult population would require an oral glucose tolerance test (OGTT). Increasing the FPG cut point to 6.1 mmol/l (110 mg/dl) or using Hb[A.sub.1c], instead of FPG to determine the need for an OGTT in people with risk factors reduced sensitivity, increased specificity and PPV, and reduced the proportion requiring an OGTT. However, each of these protocol variations substantially reduced the detection of IGT or IFG.

CONCLUSIONS--The Australian screening protocol identified one new case of diabetes for every 32 people screened, with 4 of 10 people screened requiring FPG measurement and 1 in 5 requiring an OGTT. In addition, 1 in 11 people screened had IGT or IFG. Including Hb[A.sub.1c] measurement substantially reduced both the number requiring an OGTT and the detection of IGT or IFG.

CRA/Rio Tinto in the 1990s : a decade of deunionisation

Given the scale of Rio Tinto's battles with the Australialn union movement during the roll out of its deunionisation program throughout its diverse miniing and manufacturing operations, there is much to be learnt from examining how the company first introduced its 'staff' employment system at its Tiwai Point smelter in New Zealand in 1991. Hamersley Iron in 1993, and at its Comalco-run Bell Bay and Weipa operations during 1994-96. More importantly, however, it is worth knowing why the company was so successful in deunionising previously 'soldered on' union territory. Though no doubt assisted by sympathetic legal, political and economic environments, it was ultimately the demonstrationl of managerial strength and determination, coupled with a hesitant union leadership, which led to the success of the company's deunionisation strategy. As the union movemenlt makes tenative steps to attract workers back to the fold, there are valuable lessons to be gained from analysing these momentous events which constitute such a transformational period in the history of Australian industrial relations.

Stakeholder satisfaction with the Australian Rheumatology Association Database (ARAD)

Background: The Australian Rheumatology Association Database (ARAD) is a voluntary national registry for monitoring the long-term benefits and safety of biological disease-modifying anti-rheumatic drugs (bDMARDs) for inflammatory arthritis. Both rheumatologists and patients contribute data to the ARAD.

Objective: To evaluate the satisfaction of patients and rheumatologists with the ARAD.

Methods: Cross-sectional surveys were distributed to a random sample of 100 community-dwelling ARAD patients in 2007 and to rheumatologists attending the 2007 AustralianRheumatologyAssociation (ARA) annual scientific meeting.

Survey questions included items about the usefulness of the ARAD, workload for participants, frequency of questionnaires, and experience of contact with ARAD staff.

Results: A total of 92.5% of patients perceived the ARAD as very important (scoring 9-10 on a numeric rating scale). Patients reported minimal difficulty in completing questionnaires, and 95.0% indicated that a 6-month interval between questionnaires was reasonable. Of responding rheumatologists, 32.3%, 62.1%, and 53.8% indicated that the ARAD was very important (scoring 8-10) with respect to clinical information, research, and the profession, respectively, while 68% of those participating in the ARAD reported that the workload required to enroll patients was manageable and 30% found it difficult or onerous.

Conclusion: Key stakeholders in the ARAD view it as an important resource and are satisfied with its operations. Efforts will be directed towards assisting those rheumatologists who find the associated workload difficult and to improving the perceived clinical value of information available from the ARAD.

Brave spirits on new paths : toward a globally relevant paradigm of Indigenous entrepreneurship research

This is the first study in a series aimed at strengthening research in the emerging field of Indigenous entrepreneurship. A literature survey revealed two dominant themes: the need to reconcile tradition with innovation and the need to understand how Indigenous world-views and values impact upon enterprise. Four relevant theoretical contexts guided an empirical investigation employing depth interviews with 40 selected opinion leaders representing two cultures: Indigenous Australian and American Indian. Data evaluation culminated in the formal articulation of a paradigm for Indigenous entrepreneurship research. Discussion focused on utility of the paradigm and future research directions.

Procedural justice and tax compliance

Throughout the 1990s, tens of thousands of Australian taxpayers invested in mass-marketed tax effective schemes. They enjoyed generous tax breaks until the Australian Taxation Office (ATO) told them in 1998 that they abused the system. This study examines the circumstances surrounding taxpayers' decision to invest in scheme arrangements. It also explores investors' perceptions of the way the ATO handled the schemes issue and, perhaps more importantly, why such a large number of investors defied the ATO's demands that they pay back taxes. Data were taken from in-depth interviews conducted with 29 scheme investors. Consistent with the procedural justice literature, the findings revealed that many of the scheme investors interviewed defied the ATO's demands because the procedures the ATO used to handle the situation were perceived to be unfair. Given these findings, it will be argued that to effectively shape desired behaviour, regulators will need to move beyond enforcement strategies linked purely to deterrence. A strategy that aims to emphasise the procedural justice aspects of a regulatory encounter will be discussed.

Cooperative relaying in wireless sensor networks

Cooperative relaying has been shown to be an effective method to significantly improve the error-rate performance in wireless networks. This technique combats fading by exploiting the spatial diversity made available through cooperating nodes that relay signals for each other. In the context of wireless sensor networks, cooperative relaying can be applied to reduce the energy consumption in sensor nodes and thus extend the network lifetime. Realizing this benefit, however, requires a careful incorporation of this technique into the routing process to exploit diversity gains. In this chapter, we introduce the basic concepts required to understand cooperative relaying and review current state of the art energy-efficient routing protocols that realize cooperative relaying.

Energy-efficient medium access control in wireless sensor networks

Medium access control for wireless sensor networks has been an active
research area in the past decade. This chapter discusses a set of important medium access control (MAC) attributes and possible design trade-offs in protocol design, with an emphasis on energy efficiency. Then we categorize existing MAC protocols into five groups, outline the representative protocols, and compare their advantages and disadvantages in the context of wireless sensor network. Finally, thoughts for practitioners are presented and open research issues are also discussed.

Pocket books of engagement : a 'just-in- time' framework for a high quality first year student experience

This paper describes a 'just-in-time' engagement framework for a high quality first year experience ('FYE'). The concept 'just-in-time' refers to a student-centered timeline for a managed learning environment based on the week-to-week experiences faced by a first year student in an Australian University semester. The engagement framework detailed in this paper consists of a series of teaching strategies embedded as part of a designed, integrated and co-ordinated first year program, expanding on the transition blueprint of Nelson, Kift, Humphreys & Harper (2006), working within a transition pedagogy (Kift, 2008) and implementing an institutional-wide program of collaborative engagement. This paper discusses the application of this framework to a first year foundational unit in the Bachelor of Laws degree at Deakin University, Victoria, Australia, implemented as part of an embedded institutional-wide transition program.

Variations in vascular access flows in haemodialysis can depend on needle orientation

Introduction: While using the Transonic Qc[TM] machine to assess access flow in arteriovenous fistulae (AVF), we observed that when compared to antegrade arterial needle insertion, retrograde arterial needle insertion could regularly produce lower access flow measurements. This study sought to explore this phenomenon.

Method: 23 patients entered and 20 finished the study. Patient selection criteria included: functioning AVF and an adequate AVF length for either retrograde or antegrade arterial needle insertion. After ensuring stable and similar blood pressures, 3 flow measurements were taken during the first 2 hours on the same dialysis day of 3 consecutive weeks using antegrade needle insertion then were repeated on 3 further consecutive weeks using retrograde insertion.

Results: Overall, access flows measured with retrograde insertion were significantly lower by a mean difference of 107.15 ml/min (57-484 ml/min) than the flows measured with antegrade needle placement. In 5/20, 3 recorded minimal difference and 2 had a higher access flows during retrograde insertion. No recirculation was observed during either antegrade or retrograde needle insertion. The paired t-test showed that there was significant difference between the antegrade versus retrograde mean measurements (p = 0.005).

Conclusion: Although the sample size is small and the number of measurements limited, we conclude that access flows may be greater with an antegrade arterial orientation compared to flows recorded with a retrograde orientation. The phenomenon behind this conclusion is yet to be investigated. We suggest that when using the Transonic Qc[TM] access measurement device the arterial needle should always be in the same direction for each measurement for each individual patient.