Daniel Hackett

The University of Sydney · Discipline of Exercise and Sport Science

Davies, TB, Halaki, M, Orr, R, Mitchell, L, Helms, ER, Clarke, J, and Hackett, DA. Effect of set structure on upper-body muscular hypertrophy and performance in recreationally trained men and women. J Strength Cond Res 36(8): 2176–2185, 2022—This study explored the effect of volume-equated traditional-set and cluster-set structures on muscular hype...

Objectives To examine the effect of total repetitions per set on local muscular endurance (LME) assessed via maximal repetitions to concentric muscular failure using loads based on a percentage of pre-intervention one-repetition maximum (%1RMPRE) and post-intervention 1RM (%1RMPOST). News Four electronic databases were searched using terms related...

This study investigated whether muscular strength and local muscular endurance (LME) influences accuracy of estimated repetitions to failure (ERF) during resistance exercise. Twenty resistance-trained males (age 26.3 ± 6.9 years) completed five sets of 10 repetitions at 70% 1RM for the bench press and squat. Following the 10th repetition of each se...

Background: HIV-related sarcopenia is an emerging health issue that often remains undiagnosed and can lead to reduced quality of life, independence, and premature death if untreated. This study investigated the effects of a 6 month combined training (resistance plus aerobic exercise) (CT) intervention on diagnostic measures of sarcopenia, includin...

Background: Similar muscle performance adaptations have been shown following volume-equated resistance training using cluster (CLUS) versus traditional (TRAD) set structures. This study aimed to examine the effects of higher-volume CLUS compared to lower-volume TRAD set structures on muscle performance. Methods: Twenty resistance-trained males (...

Objective To investigate through a pilot study the acute cardiorespiratory responses during functional electrical stimulation (FES) cycling, arm cranking exercise (ACE) and a combination of ACE and FES cycling (Hybrid FES cycling) in people with advanced multiple sclerosis (MS) to provide preliminary guidance for effective aerobic exercise prescrip...

Aim This systematic review aimed to determine the effect of aerobic exercise interventions, including high-intensity interval training (HIIT) and moderate-intensity continuous training (MICT), on liver fat in adults. A secondary aim was to investigate the interaction between total weekly exercise volume and exercise-related energy expenditure and c...

Background Powerlifting exercises are commonly performed by athletes and recreational trainers for increasing muscle strength. Increased performance for these exercises may promote beneficial outcomes, especially in terms of bone health. The aim of this study was to examine whether powerlifting exercise performance and muscle mass indices are assoc...

This exploratory clinical case report presents an 87-year-old man who began bodybuilding at the age of 76 years and was officially recognised as the world’s oldest competitive bodybuilder, competing until age 83. He has a background of complex health conditions including polio, strokes, cardiac arrest, atrial fibrillation, prostate disease, osteoar...

Affective responses and enjoyment of exercise mediate exercise adherence, but previous research findings have failed to examine nuances that may moderate this relationship. We examined the effects of exercise on affective and enjoyment responses during and post exercise through a systematic literature review and meta-regression analysis. We searche...

Background/aims High-intensity power training has been shown to be effective in improving muscular capabilities, functional performance and health-related quality of life in populations with physical impairments. However, the effectiveness of high-intensity power training in people with Charcot–Marie–Tooth disease remains uncertain. This case serie...

Background: A paucity of research exists examining whether resistance training with a greater number of sets per exercise enhances the development of muscular endurance. The aim of this study was to investigate the effects of ten sets versus five sets of resistance training on muscle endurance. Methods: Fifteen healthy males (age 23.7 ± 4.6 y) w...

Davies, TB, Halaki, M, Orr, R, Mitchell, L, Helms, ER, Clarke, J, and Hackett, DA. Effect of set structure on upper-body muscular hypertrophy and performance in recreationally trained men and women. J Strength Cond Res XX(X): 000-000, 2021-This study explored the effect of volume-equated traditional-set and cluster-set structures on muscular hypert...

Background: Diminished respiratory muscle has been shown following a strenuous bout of sit-ups however there is a paucity of evidence for this effect following a strenuous upper and lower body resistance training session. This study investigated the acute effect of a highvolume compared to a low-volume resistance exercise session on respiratory mu...

Hackett, DA Training, supplementation, and pharmacological practices of competitive male bodybuilders across training phases. J Strength Cond Res XX(X): 000-000, 2021-Bodybuilding involves the pursuit of muscularity and leanness primarily through the use of progressive resistance training in combination with other practices such as manipulation of...

To evaluate the effect of combined resistance and aerobic training (RT+AT) on regional bone mineral density (BMD) and physical performance in people living with HIV (PLWH). Forty PLWH (20 men and 20 women) were randomized into RT+AT group (n=20; age = 38.3 ± 4.9) or non‐exercise control group (n=20; age = 37.9 ± 5.1). The RT+AT group was required...

Background Reductions in muscle size and strength occur with aging. These changes can be mitigated by participation in resistance training. At present, it is unknown if sex contributes to differences in adaptation to resistance training in older adults. Objective The aim of this systematic review was to determine if sex differences are apparent in...

Hackett, DA. Influence of movement velocity on accuracy of estimated repetitions to failure in resistance-trained men. J Strength Cond Res XX(X): 000-000, 2021-This study explored the accuracy in estimated repetitions to failure (ERF) and changes in mean concentric velocity (MCV) during resistance exercise. Twenty male resistance trainers (age, 26....

The aim of this study was to examine whether lung function and respiratory muscle strength are associated with weightlifting strength and body composition in non-athletic males. A total 51 males with resistance training experience participated. One-repetition maximum tests were performed for the bench press, squat and deadlift and body composition...

Diverse exercise-induced adaptations following aerobic endurance compared to strength-training programs is well documented, however, there is paucity of research specifically focused on adaptations in the respiratory system. The aim of the study was to examine whether differences in lung function and respiratory muscle strength exist between traine...

Background: A paucity of research exits concerning physiological factors influencing heart structure and function in strength athletes. This pilot study investigated whether body composition and muscle performance is associated with indices of cardiac structure and function in experienced resistance trainers. Methods: A cross-sectional study des...

For a short time this eprint link to the full article is now ready to use and is: https://www.tandfonline.com/eprint/MQZ3ZNVGD8RPECFZDE9V/full?target=10.1080/02640414.2020.1851926 Abstract Field-based tests including the medicine ball chest throw (MBCT) and vertical jump are used to assess muscle performance. To date no study has compared perform...

Background Breast lymphoedema can occur following surgical treatment for breast cancer. We investigated whether an exercise program reduced breast lymphoedema symptoms compared to a non-exercise control group.MethodsA single-blinded randomised controlled trial was conducted in which women with stable breast lymphoedema (n = 89) were randomised into...

The aim of this study was to examine whether a high-volume compared to low-volume resistance exercise session acutely impairs lung function. Fourteen males (age 23.8±6.5 years) with resistance training experience participated in this study. Participants completed two resistance training protocols (high- and low-volume) and a control session (no exe...

Longitudinal research on training and dietary practices of natural powerlifters is limited. This study investigated the effect of phases of training on physical and physiological parameters in male natural powerlifters. Nine participants completed testing at two time points: (i) preparatory phase (~3 months prior to a major competition) and (ii) co...

Background The effect of resistance training (RT) on adaptations in muscular strength and hypertrophy has never been examined in an exclusively female synthesis of the literature. Objective The objectives of this study were threefold: (1) to systematically review the literature on female adaptations to RT, characterising the effect in terms of mus...

The ability to accurately identify proximity to momentary failure during a set of resistance exercise might be important to maximise training adaptations. This study examined the association between perceptual fatigue and the accuracy of the estimated repetitions to failure (ERF). Twenty-seven males and eleven females performed sets of 10 repetitio...

Background: Inspiratory muscle training has been shown to improve exercise performance, however there is limited evidence for its effectiveness in soccer players. This study investigates the effect of inspiratory muscle training on soccer-specific fitness and exercise tolerance in adolescent male players. Methods: Thirty highly trained soccer pl...

Context: Physical activity for women with early-stage breast cancer is well recognized for managing cancer-related symptoms and improving quality of life. While typically excluded from interventions, women with metastatic breast cancer may also benefit from physical activity. Objective: To 1) determine the safety and feasibility of a physical ac...

This study investigated the effects of high-load cluster- vs. traditional-set structures using the bench press on velocity and power. Twenty-one resistance-trained individuals (male512, female59) performed a 3-week familiarization block followed by randomization into 1 of 2 upper- and lower-body split training routines performed for 8 weeks. The be...

Previous research has shown that kettlebell swings (KBS), utilizing the hip-hinge technique, exhibit similar lower-limb muscle activation patterns to sprint running. This study investigated whether the inclusion of KBS in the warm-up enhances sprint performance. Moderately trained males (n = 12) and females (n = 8) performed KBS and a control (CON)...

Fast bowlers have the highest injury rates in cricket; therefore, reducing these injuries is a priority for coaches and the support staff. Improving physical conditioning and monitoring bowling workload are primary preventative strategies to reduce overuse injuries. The objective of this study was to investigate practices of cricket coaches in Aust...

The purpose of this systematic review and meta-analysis is to assess the effect of concurrent high intensity interval training (HIIT) and resistance training (RT) on strength and hypertrophy. Five electronic databases were searched using terms related to HIIT, RT, and concurrent training. Effect size (ES), calculated as standardised differences in...

This study aimed to describe the body composition and physiological changes which take place during the in-season and recovery periods of a group of natural bodybuilders. Natural male bodybuilders (n = 9) were assessed 16 (PRE16), 8 (PRE8), and 1 (PRE1) week(s) before, and 4 (POST4) weeks after a bodybuilding competition. Assessments included body...

Currently, it is unclear whether manipulation of movement velocity during resistance exercise has an effect on hypertrophy of specific muscles. The purpose of this systematic review of literature was to investigate the effect of movement velocity during resistance training on muscle hypertrophy. Five electronic databases were searched using terms r...

This study investigated the effect of a 12-week modified German Volume Training intervention, or the 10 sets method, on muscle strength and hypertrophy. Twelve healthy males were randomly assigned to either a 5-SET or 10-SET group and performed 5 or 10 sets, respectively, of 10 repetitions at 60-80% one-repetition maximum (1RM). Muscle strength and...

The purpose of this study was to 1) examine the accuracy of Estimated Repetitions to Failure (ERF) during resistance exercise between two sessions, and 2) compare ERF to RPE (Rating of Perceived Exertion) for determining proximity to momentary failure. Forty-eight adults with recreational resistance training experience performed 3 sets of 10 repeti...

It remains unclear whether training in fasted compared to fed states leads to greater weight loss and whether this practice results in beneficial or detrimental changes in body composition. We conducted a systematic review to examine the effect of overnight-fasted versus fed exercise on weight loss and body composition. Seven electronic databases w...

Aim: To investigate whether the amount and distribution of lean body mass and fat mass is associated with disease severity in adults with Charcot-Marie Tooth. Methods: Ten participants (age 46 ± 13 y, height 1.7 ± 0.1 m, and body mass 77 ± 17 kg) with Charcot-Marie Tooth disease were involved in this study. Participants were evaluated for qualit...

This study examined the predictive ability of the medicine ball chest throw and vertical jump for muscular strength and power in adolescents. One hundred and ninety adolescents participated in this study. Participants performed trials of the medicine ball chest throw and vertical jump, with vertical jump peak power calculated via an estimation equa...

Despite exercise or physical activity (PA) being effective on depression and weight management generally, its effectiveness remains uncertain during postpartum. This systematic review aimed to determine the efficacy of exercise or PA interventions on postnatal depression (PND) and weight loss, with a subsequent aim to identify more effective interv...

Competitive bodybuilders undergo strict dietary and training practices to achieve an extremely lean and muscular physique. The purpose of this study was to identify and describe different dietary strategies used by bodybuilders, their rationale, and the sources of information from which these strategies are gathered. In-depth interviews were conduc...

Background: Movement velocity is an acute resistance-training variable that can be manipulated to potentially optimize dynamic muscular strength development. However, it is unclear whether performing faster or slower repetitions actually influences dynamic muscular strength gains. Objective: We conducted a systematic review and meta-analysis to...

Muscle dysmorphia (MD) is characterized by the pathological pursuit of muscularity and leanness, which includes eating-and exercise-related practices. The aim of this cross-sectional study was to identify correlations of MD symptomatology in natural bodybuilders. An online survey assessing diet, supplementation and training practices, and MD and ea...

Background Muscle dysmorphia (MD) is associated with a self-perceived lack of size and muscularity, and is characterized by a preoccupation with and pursuit of a hyper-mesomorphic body. MD symptoms may hypothetically be more prevalent in bodybuilders (BBs) than in non-bodybuilder resistance trainers (NBBRTs). Objective Our objective was to compare...

Tryptophan loading enhances sleep quality by increasing the ratio of plasma tryptophan to large neutral amino acids (TRP:LNAA) and consequently synthesis and availability of serotonin in the brain. Alpha-lactalbulmin (A-LAC) is rich in tryptophan and has the highest TRP:LNAA of all protein sources. This pilot study investigated the effect of an eve...

Muscle dysmorphia (MD) is characterized by the pathological pursuit of muscularity and leanness, which includes eating- and exercise-related practices. The aim of this cross-sectional study was to identify correlations of MD symptomatology in natural bodybuilders. An online survey assessing diet, supplementation and training practices, and MD and e...

German Volume Training (GVT), or the 10 sets method, has been used for decades by weightlifters to increase muscle mass. To date, no study has directly examined the training adaptations following GVT. The purpose of this study was to investigate the effect of a modified GVT intervention on muscular hypertrophy and strength. Nineteen healthy males w...

Charcot-Marie-Tooth (CMT) is a rare inherited peripheral neuropathy in which quality of life (QoL) is reduced compared to the general population. This paper investigates the relationship between QoL and physical performance in people with CMT with the aim of identifying avenues for future research into rehabilitation strategies. Cross-sectional dat...

The primary aim of this study was to assess the accuracy in estimation of repetitions to failure (ERF) during resistance exercise. Further, this investigation examined whether the accuracy in ERF was affected by training status, sex, or exercise type. Eighty-one adults (males, n = 53 and females, n = 28) with broad range of resistance training expe...

Aims: Regular aerobic exercise reduces visceral adipose tissue (VAT) and liver fat, however not all individuals are able to adopt and adhere to such programs. Progressive resistance training (PRT) may be an alternative therapy, but there is limited available evidence. We examined the efficacy of PRT as per current exercise guidelines, compared wit...

Search strategy flow diagram.

Results of the modified from Downs et al. [15] methodological quality assessment

The purpose of this study was to examine the effect of regular exercise training on insulin sensitivity in adults with type 2 diabetes mellitus (T2DM) using the pooled data available from randomised controlled trials. In addition, we sought to determine whether short-term periods of physical inactivity diminish the exercise-induced improvement in i...

This systematic review with a meta-analysis of studies was carried out to evaluate the potential of overwork weakness on the basis of grip strength of dominant and nondominant hands in individuals with Charcot-Marie-Tooth disease (CMT). Numerous electronic databases were searched from the earliest records to February 2016. Studies of any design inc...

Introduction: Insulin resistance is a major part in the underlying pathology of type 2 diabetes (T2D) and has been independently associated with an increase risk of age-related chronic conditions including hypertension, CAD, stroke and cancer. Current exercise guidelines recommend that adults with T2D should undertake aerobic exercise 3 to 5 days p...

Background It remains unclear whether repetitions leading to failure (failure training) or not leading to failure (non-failure training) lead to superior muscular strength gains during resistance exercise. Failure training may provide the stimulus needed to enhance muscular strength development. However, it is argued that non-failure training leads...

Background: Intensive sport participation in childhood and adolescence is an established cause of acute and overuse injury. Interventions and programs designed to prevent such injuries are important in reducing individual and societal costs associated with treatment and recovery. Likewise, they help to maintain the accrual of positive outcomes fro...

Purpose: This systematic review was conducted to evaluate the effect of Olympic weightlifting (OW) on vertical jump (VJ) height compared to a control condition, traditional resistance training and plyometric training. Methods: Five electronic databases were searched using terms related to OW and VJ. Studies needed to include at least one OW exer...

FOR ADVANCED TRAINERS TARGETING MUSCULAR HYPERTROPHY, IT IS RECOMMENDED THAT THE MAJORITY OF TRAINING BE DEVOTED TO 6-12 REPETITIONS AT MODERATE LOADING (70-85% 1 REPETITION MAXIMUM) FOR MULTIPLE SETS, PERFORMED TO OR CLOSE TO MOMENTARY MUSCULAR FAILURE (MMF). AN ADVANCED TRAINING TECHNIQUE THAT CAN BE USED AFTER REACHING MMF IS FORCED REPETITIONS...

Charcot-Marie-Tooth disease (CMT) is a slowly progressive hereditary degenerative disease and one of the most common neuromuscular disorders. Exercise may be beneficial to maintain strength and function for people with CMT, however, no comprehensive evaluation of the benefits and risks of exercise have been conducted. A systematic review was comple...

Competitive bodybuilders are well known for extreme physique traits and extremes in diet and training manipulation to optimize lean mass and achieve a low body fat. Although many of the dietary dogmas in bodybuilding lack scientific scrutiny, a number, including timing and dosing of high biological value proteins across the day, have more recently...

Aerobic exercise reduces liver fat and visceral adipose tissue (VAT). However, there is limited data from randomized trials to inform exercise programming recommendations. This study examined the efficacy of commonly prescribed exercise doses for reducing liver fat and VAT using a randomized placebo-controlled design. Inactive and overweight/obese...

Aim: The purpose of this study was to examine whether a high--volume compared to a low--volume whole--body resistance exercise session acutely impairs lung function. Methods: Fifteen competitive male bodybuilders (age 27.4 ± 5.4 y; body mass 89.7 ± 12.8 kg; stature 177.9 ± 4.8 cm), in a crossover trial, completed two resistance training protocol...