Neil Cronin

Neil Cronin
University of Jyväskylä | JYU · Department of Biology of Physical Activity

PhD

About

104
Publications
34,854
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2,554
Citations
Additional affiliations
January 2011 - December 2012
Jyväskylän yliopisto
January 2011 - present
Griffith University
January 2007 - December 2010
Aalborg University
Education
August 2005 - January 2007
University of Jyväskylä
Field of study
  • Biomechanics
August 2002 - June 2005
Brunel University London
Field of study
  • Sport Science

Publications

Publications (104)
Article
Purpose: Muscle anatomical cross-sectional area (ACSA) can be assessed using ultrasound and images are usually evaluated manually. Here, we present DeepACSA, a deep learning approach to automatically segment ACSA in panoramic ultrasound images of the human rectus femoris (RF), vastus lateralis (VL), gastrocnemius medialis (GM) and lateralis (GL) m...
Article
Full-text available
Purpose Measurement of medial gastrocnemius (MG) tendon length using ultrasonography (US) requires the muscle–tendon junction (MTJ) to be located. Previously, the MG MTJ has been tracked from different proximo-distal locations near the MTJ, which could influence estimates of tendon length change due to the different characteristics of the aponeuros...
Article
The Achilles tendon (AT) is composed of three distinct in-series elastic subtendons, arising from different muscles in the triceps surae. Independent activation of any of these muscles is thought to induce sliding between the adjacent AT subtendons. We aimed to investigate displacement patterns during voluntary contraction (VOL) and selective trans...
Article
Full-text available
For women, menopausal transition is a time of significant hormonal changes, which may contribute to altered body composition and regional adipose tissue accumulation. Excess adiposity, and especially adipose tissue accumulation in the central body region, increases women's risk of cardiovascular and metabolic conditions and affects physical functio...
Article
Full-text available
Background Achilles tendon rupture appears to alter stiffness and length of the tendon. These alterations may affect the function of tendon in force transmission and in energy storage and recovery. We studied the mechanical properties of the Achilles' tendon post-rupture and their association with function. Methods Twenty-four (20 males, 4 females...
Article
Full-text available
Measurements of muscle-tendon unit passive mechanical properties are often used to illustrate acute and chronic responses to a training stimulus. The purpose of this study was to quantify the inter-session repeatability of triceps surae passive stiffness measurements in athletic and non-athletic populations, with the view to discussing its usefulne...
Preprint
Full-text available
Background: Muscle anatomical cross-sectional area (ACSA) is an important parameter that characterizes muscle function and helps to classify the severity of several muscular disorders. Ultrasound is a patient friendly, fast and cheap method of assessing muscle ACSA, but manual analysis of the images is laborious, subjective and requires thorough ex...
Article
Full-text available
To investigate tendon displacement patterns in non‐surgically treated patients 14‐months after acute Achilles tendon rupture (ATR), and to classify patients into groups based on their Achilles tendon (AT) displacement patterns. Twenty patients were tested. Sagittal images of AT were acquired using B‐mode ultrasonography during ramp contractions at...
Article
Full-text available
Kinematic analysis is often performed in a lab using optical cameras combined with reflective markers. With the advent of artificial intelligence techniques such as deep neural networks, it is now possible to perform such analyses without markers, making outdoor applications feasible. In this paper I summarise 2D markerless approaches for estimatin...
Article
Full-text available
Hamstring muscle function during knee flexion has been linked to hamstring injury and performance. However, it is unclear whether knee flexion alone (KF) requires similar hamstring electromyography (EMG) activity pattern to simultaneous hip extension and knee flexion (HE-KF), a combination that occurs in the late swing phase of sprinting. This stud...
Conference Paper
Introduction: Measurements of passive stiffness (PS) are often used to quantify the passive resistance of a muscle-tendon unit (MTU) to stretching, which is interesting in populations who undergo chronic loading and/or excessive stretching through exercise (Moltubakk et al., 2018). This metric may also be used to monitor the ‘neuromuscular conditi...
Article
One of the purposes of footwear is to assist locomotion, but some footwear types seem to restrict natural foot motion, which may affect the contribution of ankle plantar flexor muscles to propulsion. This study examined the effects of different footwear conditions on the activity of ankle plantar flexors during walking. Ten healthy habitually shod...
Preprint
B-mode ultrasound is commonly used to image musculoskeletal tissues, but one major bottleneck is data interpretation, and analyses of muscle thickness, pennation angle and fascicle length are often still performed manually. In this study we trained deep neural networks (based on U-net) to detect muscle fascicles and aponeuroses using a set of label...
Article
Full-text available
We mapped structural and functional characteristics of muscle‐tendon units in a population exposed to very long‐term routine overloading. Twenty‐eight military academy cadets (age: 21.00 ± 1.1 yrs; height: 176.1 ± 4.8 cm; mass: 73.8 ± 7.0 kg) exposed for over 24 months to repetitive overloading were profiled via ultrasonography with a senior subgro...
Article
Full-text available
Background and Objective Deep learning approaches are common in image processing, but often rely on supervised learning, which requires a large volume of training images, usually accompanied by hand-crafted labels. As labelled data are often not available, it would be desirable to develop methods that allow such data to be compiled automatically. I...
Article
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In midlife, women experience hormonal changes due to menopausal transition. A decrease especially in estradiol has been hypothesized to cause loss of muscle mass. This study investigated the effect of menopausal transition on changes in lean and muscle mass, from the total body to the muscle fiber level, among 47–55-year-old women. Data were used f...
Article
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New findings: What is the central question of the study? What are the effects of caffeine on neuromuscular function in a non-fatigued state and during fatiguing exercise? What is the main finding and its importance? In a non-fatigued state caffeine decreased the duration of the silent period evoked by TMS. A caffeine-induced reduction of inhibitor...
Article
Full-text available
In vivo measurements of muscle architecture (i.e. the spatial arrangement of muscle fascicles) are routinely included in research and clinical settings to monitor muscle structure, function and plasticity. However, in most cases such measurements are performed manually, and more reliable and time-efficient automated methods are either lacking compl...
Article
Introduction: Hamstring strain injuries typically occur in the proximal biceps femoris long head (BFlh) at high running speeds. Strain magnitude seems to be the primary determinant of strain injury, and may be regulated by muscle activation. In running, BFlh strain is largest in the proximal region, especially at high speeds. However, region-specif...
Article
Full-text available
Ankle plantar flexor muscles are active in the stance phase of walking to propel the body forward. Increasing walking speed requires increased plantar flexor excitation, frequently assessed using surface electromyography (EMG). Despite its popularity, validity of surface EMG applied on shank muscles is mostly unclear. Thus, we examined the agreemen...
Conference Paper
Summary: Surface and fine-wire electromyography activity of flexor hallucis longus, soleus, medial and lateral gastrocnemius and tibialis anterior muscles was measured simultaneously during walking at four different speeds to examine whether signals recorded with the two methods exhibit similar signal characteristics. We found statistical differenc...
Poster
Full-text available
Abstract: Achilles tendon rupture (ATR) is the most common tendon rupture. ATR recovery predictors are poorly understood. Early mobilization and/or weight-bearing activities seem crucial for functional outcome but their effects on later in recovery are unknown. This study is a part of clinical cohort study “Non-operative treatment of Achilles tendo...
Preprint
Full-text available
In vivo measurements of muscle architecture (i.e. the spatial arrangement of muscle fascicles) are routinely included in research and clinical settings to monitor muscle structure, function and plasticity. However, in most cases such measurements are performed manually, and more reliable and time-efficient automated methods are either lacking compl...
Article
The interaction between the Achilles tendon and the triceps surae muscles seems to be modulated differently with various task configurations. Here we tested the hypothesis that the increased forces and ankle joint work during running under contrasting conditions (altered speed or load) would be met by different, time-dependent adjustments at the mu...
Article
Full-text available
Background: During the stance phase of running, the elasticity of the Achilles tendon enables the utilisation of elastic energy and allows beneficial contractile conditions for the triceps surae muscles. However, the effect of changes in tendon mechanical properties induced by chronic loading is still poorly understood. We tested the hypothesis th...
Article
Background: In the bilateral Nordic hamstring exercise (NHE), hamstrings operate at relatively short lengths, which may limit this exercise’s efficacy in hamstring injury prevention. Objectives: To examine knee flexion torque, and biceps femoris long head (BFlh) and semitendinosus (ST) high-density electromyography (HD-EMG) activity during unilate...
Article
Full-text available
This paper describes a single body-mounted sensor that integrates accelerometers, gyroscopes, compasses, barometers, a GPS receiver, and a methodology to process the data for biomechanical studies. The sensor and its data processing system can accurately compute the speed, acceleration, angular velocity, and angular orientation at an output rate of...
Article
Kinematic analysis is often performed with a camera system combined with reflective markers placed over bony landmarks. This method is restrictive (and often expensive), and limits the ability to perform analyses outside of the lab. In the present study, we used a markerless deep learning-based method to perform 2D kinematic analysis of deep water...
Article
Full-text available
Proximal‐distal differences in muscle activity are rarely considered when defining the activity level of hamstring muscles. The aim of this study was to determine the inter‐muscular and proximal‐distal electromyography (EMG) activity patterns of hamstring muscles during common hamstring exercises. Nineteen amateur athletes without a history of hams...
Conference Paper
Introduction: Exercise induces mental health benefits. A member of the neurotrophin family, brain-derived neurotrophic factor (BDNF), plays a crucial role in these exercise-induced effects (Huang et al., 2014). In mice, BDNF synthesis and its modulation of synaptic transmission in the hippocampus are facilitated by the activation of adenosine recep...
Conference Paper
Full-text available
ECSS 2018 Dublin 05.07.2018 - 18:00 - 19:30, Lecture room: WICKLOW MEETING ROOM 2 INTRODUCTION: Nordic hamstring exercise (NHE) is a popular injury prevention and rehabilitation exercise. Conventionally, NHE is performed bilaterally and with extended hip joint, i.e. at a relatively short muscle length. According to Askling et al. (2013), exercises...
Conference Paper
Full-text available
Ankle plantar flexors substantially contribute to propulsion in human walking, and their relative contributions may be affected by the type of footwear used. In this study, we aimed to examine plantar flexor fine-wire electromyography (wEMG) activity in different footwear types and barefoot walking. We further examined the effect of walking speed o...
Conference Paper
Full-text available
BACKGROUND AND AIM: Ergogenic effects of caffeine have been extensively reported, but its mechanisms of action are not yet fully understood. Furthermore, there is a large inter-individual variability of the responsiveness to this drug. Thus, there is an increased likelihood of encountering a masked effect of responders that cannot statistically be...
Article
Full-text available
During rapid deceleration of the body, tendons buffer part of the elongation of the muscle–tendon unit (MTU), enabling safe energy dissipation via eccentric muscle contraction. Yet, the influence of changes in tendon stiffness within the physiological range upon these lengthening contractions is unknown. This study aimed to examine the effect of tr...
Article
Recent studies suggest region-specific metabolic activity in hamstring muscles during injury prevention exercises, but the neural representation of this phenomenon is unknown. The aim of this study was to examine whether regional differences are evident in the activity of biceps femoris long head (BFlh) and semitendinosus (ST) muscles during two co...
Article
Full-text available
The compliance of elastic elements allows muscles to dissipate energy safely during eccentric contractions. This buffering function is well documented in animal models but our understanding of its mechanism in humans is confined to non-specific tasks, requiring a subsequent acceleration of the body. The present study aimed to examine the behaviour...
Conference Paper
Introduction Elite athletes are expected to perform at their highest level repeatedly within short time periods. This quick turnaround may not always allow for adequate recovery of the neuromuscular system, diminishing subsequent performance (Reilly and Ekblom, 2005). Cold water immersion (CWI) is a widely popular method implemented to aid in the r...
Article
Full-text available
Background: As sedentary behavior is a global health issue, there is a need for methods of self-reported sitting assessment. The accuracy and reliability of these methods should also be tested in various populations and different cultural contexts. This study examined the validity of long-term and short-term recall of occupational sitting time in...
Article
Purpose: While merely standing up interrupts sedentary behavior, it is important to study acute metabolic responses during single bouts of sitting and standing to understand the physiological processes affecting the health of office workers. Methods: 18 healthy middle aged women aged 49.4 ± 7.9 years (range: 40 to 64) with a BMI of 23.4 ± 2.8 kg...
Conference Paper
Full-text available
Background: As one of the most popular sports in the world, soccer (football association) is played by thousands of amateurs and professional players across the globe. The participation in this sports increases the overall risk of injury. Of all injuries, hamstring strain injuries have been shown to be the most common sub-type of injury resultan...
Article
Post-activation potentiation can improve athletic performance, but the underlying mechanisms are poorly understood. This study investigated the effect of conditioning hops on triceps surae muscle force and tendon strain and its contribution to potentiated stretch-shortening cycle (SSC) performance. Thirty-two subjects participated in two experiment...
Article
Ankle plantar flexor muscles support and propel the body in the stance phase of locomotion. Besides the triceps surae, flexor hallucis longus muscle (FHL) may also contribute to this role, but very few in vivo studies have examined FHL function during walking. Here, we investigated FHL fascicle behavior at different walking speeds. Ten healthy male...
Thesis
Full-text available
Soccer is played by thousands of athletes across the globe and its participation increases the overall risk of injury, in particular, hamstring strain injuries (HSI). Biceps femoris (BF) has been shown to be involved the in 5 out of 6 HSI cases and risk factors including fatigue and short BF fascicle length (FL) have been identified. Furthermore, p...
Article
Full-text available
The bilateral deficit phenomenon, characterized by a reduction in the amount of force from a single limb during maximal bilateral actions, has been shown in various movement tasks, contraction types and different populations. However, bilateral deficit appears to be an inconsistent phenomenon, with high variability in magnitude and existence, and s...
Article
Full-text available
PurposeInterhemispheric inhibition may play a role in the expression of bilateral deficit in force (BLD). This study investigated whether the degree of BLD is reflected in the nature of interhemispheric interaction during unilateral and bilateral contractions. Methods Subjects divided into three groups, ‘bilateral’ (n = 7), ‘unilateral’ (n = 5) and...
Article
Stretching can decrease a muscle's maximal force, whereas short but intense muscle contractions can increase it. We hypothesized that when combined, postactivation potentiation induced by reactive jumps would counteract stretch-induced decrements in drop jump (DJ) performance. Moreover, we measured changes in muscle twitch forces and ankle joint st...
Article
This study examined the contributions of individual muscles to changes in energetic cost of transport (COT) over seven walking speeds, and compared results between healthy young and elderly subjects. Twenty six participants (13 young aged 18-30; 13 old aged 70-80) were recruited. COT (O2/kg body mass/km) was calculated by standardizing the mean oxy...
Presentation
Full-text available
Introduction It has been shown that a set of maximal reactive hops can induce post-activation potentiation in the triceps surae muscle and enhance drop jump (DJ) performance (Bergmann et al., 2013). The underlying mechanisms are not yet clear. In the present study we hypothesized that hops could modulate muscle-tendon interaction, facilitating high...
Article
Purpose: Older adults walk slower than young adults but it is not known why. Previous research suggests that ankle plantarflexors may have a crucial role in the reduction of walking speed. The purpose of this study was to investigate age-related differences in triceps surae muscle-tendon function during walking to further investigate the role of p...
Conference Paper
CHRONIC MECHANICAL OVERLOADING THROUGH WALKING, MARCHING AND JOGGING DOES NOT INDUCE CHANGES IN MUSCLE-TENDON MORPHOLOGY Bissas, A.1, Havenetidis, K.2, Metaxas, T.I.3, Christoulas, K.3, Cronin, N.J.4 1: Leeds Beckett University (UK), 2: Hellenic Army Academy (Greece), 3: University of Thessaloniki (Greece), 4: University of Jyväskylä (Finland) In...
Conference Paper
Bissas, A.1, Havenetidis, K.2, Metaxas, T.I.3, Christoulas, K.3, Cronin, N.J.4 1: Leeds Beckett University (UK), 2: Hellenic Army Academy (Greece), 3: University of Thessaloniki (Greece), 4: University of Jyväskylä (Finland) Introduction Muscle-tendon morphological properties have been extensively examined in a wide range of populations (e.g. S...
Conference Paper
Bissas, A.1, Havenetidis, K.2, Metaxas, T.I.3, Christoulas, K.3, Cronin, N.J.4 1: Leeds Beckett University (UK), 2: Hellenic Army Academy (Greece), 3: University of Thessaloniki (Greece), 4: University of Jyväskylä (Finland) Introduction Muscle-tendon morphological properties have been extensively examined in a wide range of populations (e.g....
Article
Racewalking is a unique event combining mechanical elements of walking with speeds associated with running. It is currently unclear how racewalking technique impacts upon lower limb muscle-tendon function, despite the relevance of this to muscle economy and overall performance. The present study examined triceps surae neuromechanics in 11 internati...
Article
Full-text available
Cite this paper as: Péter A, Hegyi A, Tihanyi J, Cronin NJ. 2016. Function of the flexor hallucis longus muscle – what do we know? Hungarian Review of Sport Science. 17 (65): 46-50. Flexor hallucis longus (FHL) muscle has several functions, including plantarflexion of the ankle, flexion of the big toe and support of the medial longitudinal arch.T...
Article
Full-text available
Background Reflex excitability is increased in hemiplegic patients compared to healthy controls. One challenge of stroke rehabilitation is to decrease the effects of hyperreflexia, which may be possible with water immersion. Methods/Aims The present study examined the effects of acute water immersion on electrically-evoked Hmax:Mmax ratios (a meas...
Article
Reducing sitting time by means of sit–stand workstations is an emerging trend, but further evidence is needed regarding their health benefits. This cross-sectional study compared work time muscle activity patterns and spinal shrinkage between office workers (aged 24–62, 58.3% female) who used either a sit–stand workstation (Sit–Stand group, n = 10)...
Article
Lateral connections between muscles provide pathways for myofascial force transmission. To elucidate whether these pathways have functional roles in vivo, we examined whether activation could alter the shear between the soleus (SOL) and lateral gastrocnemius (LG) muscles. We hypothesized that selective activation of LG would decrease the stretch-in...
Article
Sit-stand workstations offer a potential strategy to reduce prolonged occupational sitting. This controlled intervention study examined the effects of an environmental intervention on occupational sedentary time, musculoskeletal comfort and work ability, and the usability of sit-stand workstations in office work via a self-reported questionnaire. T...
Article
Previous studies have shown that aging is associated with alterations in muscle architecture and tendon properties. However, the possible influence of different types of regular exercise loading on muscle architecture and tendon properties in older adults is poorly understood. To address this, triceps surae muscle-tendon properties were examined in...
Article
Activation of skeletal muscle twice in quick succession results in nonlinear force summation (i.e. doublet potentiation). The force contributed by a second activation is typically of augmented amplitude, longer in duration and generated at a greater rate. The purpose of this study was to examine force summation in a muscle attached to a compliant t...
Article
Large forces are generated under the big toe in the push-off phase of walking. The largest flexor muscle of the big toe is the flexor hallucis longus (FHL), which likely contributes substantially to these forces. This study examined FHL function at different levels of isometric plantarflexion torque and in the push-off phase at different speeds of...
Article
Human leg muscles are often activated inhomogeneously, e.g. in standing. This may also occur in complex tasks like walking. Thus, bipolar surface electromyography (sEMG) may not accurately represent whole muscle activity. This study used 64-electrode high-density sEMG (HD-sEMG) to examine spatial variability of lateral gastrocnemius (LG) muscle act...