1
|
Tanji F, Ohnuma H, Ando R, Yamanaka R, Ikeda T, Suzuki Y. Longer Ground Contact Time Is Related to a Superior Running Economy in Highly Trained Distance Runners. J Strength Cond Res 2024; 38:985-990. [PMID: 38349337 DOI: 10.1519/jsc.0000000000004737] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/04/2024]
Abstract
ABSTRACT Tanji, F, Ohnuma, H, Ando, R, Yamanaka, R, Ikeda, T, and Suzuki, Y. Longer ground contact time is related to a superior running economy in highly trained distance runners. J Strength Cond Res 38(5): 985-990, 2024-Running economy is a key component of distance running performance and is associated with gait parameters. However, there is no consensus of the link between the running economy (RE), ground contact time, and footstrike patterns. Thus, this study aimed to clarify the relationship between RE, ground contact time, and thigh muscle cross-sectional area (CSA) in highly trained distance runners and to compare these parameters between 2 habitual footstrike patterns (midfoot vs. rearfoot). Seventeen male distance runners ran on a treadmill to measure RE and gait parameters. We collected the CSAs of the right thigh muscle using a magnetic resonance imaging scanner. The RE had a significant negative relationship with distance running performance ( r = -0.50) and ground contact time ( r = -0.51). The ground contact time had a significant negative relationship with the normalized CSAs of the vastus lateralis muscle ( r = -0.60) and hamstrings ( r = -0.54). No significant differences were found in RE, ground contact time, or normalized CSAs of muscles between midfoot ( n = 10) and rearfoot ( n = 7) strikers. These results suggest that large CSAs of knee extensor muscles results in short ground contact time and worse RE. The effects of the footstrike pattern on the RE appear insignificant, and the preferred footstrike pattern can be recommended for running in highly trained runners.
Collapse
Affiliation(s)
- Fumiya Tanji
- Department of Competitive Sports, Tokai University, Kanagawa, Japan
| | - Hayato Ohnuma
- Faculty of Education, Kansai University of Social Welfare, Hyogo, Japan
| | - Ryosuke Ando
- Center for General Education, Tokyo Keizai University, Tokyo, Japan
- Department of Sport Science and Research, Japan Institute of Sports Sciences, Tokyo, Japan
| | - Ryo Yamanaka
- Faculty of Agro-Food Science, Niigata Agro-Food University, Niigata, Japan; and
| | - Tatsuaki Ikeda
- Tochigi Institute of Sports Medicine and Science, Tochigi, Japan
| | - Yasuhiro Suzuki
- Center for General Education, Tokyo Keizai University, Tokyo, Japan
| |
Collapse
|
2
|
Van Hooren B, Jukic I, Cox M, Frenken KG, Bautista I, Moore IS. The Relationship Between Running Biomechanics and Running Economy: A Systematic Review and Meta-Analysis of Observational Studies. Sports Med 2024; 54:1269-1316. [PMID: 38446400 PMCID: PMC11127892 DOI: 10.1007/s40279-024-01997-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/24/2024] [Indexed: 03/07/2024]
Abstract
BACKGROUND Running biomechanics is considered an important determinant of running economy (RE). However, studies examining associations between running biomechanics and RE report inconsistent findings. OBJECTIVE The aim of this systematic review was to determine associations between running biomechanics and RE and explore potential causes of inconsistency. METHODS Three databases were searched and monitored up to April 2023. Observational studies were included if they (i) examined associations between running biomechanics and RE, or (ii) compared running biomechanics between groups differing in RE, or (iii) compared RE between groups differing in running biomechanics during level, constant-speed, and submaximal running in healthy humans (18-65 years). Risk of bias was assessed using a modified tool for observational studies and considered in the results interpretation using GRADE. Meta-analyses were performed when two or more studies reported on the same outcome. Meta-regressions were used to explore heterogeneity with speed, coefficient of variation of height, mass, and age as continuous outcomes, and standardization of running shoes, oxygen versus energetic cost, and correction for resting oxygen or energy cost as categorical outcomes. RESULTS Fifty-one studies (n = 1115 participants) were included. Most spatiotemporal outcomes showed trivial and non-significant associations with RE: contact time r = - 0.02 (95% confidence interval [CI] - 0.15 to 0.12); flight time r = 0.11 (- 0.09 to 0.32); stride time r = 0.01 (- 0.8 to 0.50); duty factor r = - 0.06 (- 0.18 to 0.06); stride length r = 0.12 (- 0.15 to 0.38), and swing time r = 0.12 (- 0.13 to 0.36). A higher cadence showed a small significant association with a lower oxygen/energy cost (r = - 0.20 [- 0.35 to - 0.05]). A smaller vertical displacement and higher vertical and leg stiffness showed significant moderate associations with lower oxygen/energy cost (r = 0.35, - 0.31, - 0.28, respectively). Ankle, knee, and hip angles at initial contact, midstance or toe-off as well as their range of motion, peak vertical ground reaction force, mechanical work variables, and electromyographic activation were not significantly associated with RE, although potentially relevant trends were observed for some outcomes. CONCLUSIONS Running biomechanics can explain 4-12% of the between-individual variation in RE when considered in isolation, with this magnitude potentially increasing when combining different variables. Implications for athletes, coaches, wearable technology, and researchers are discussed in the review. PROTOCOL REGISTRATION https://doi.org/10.17605/OSF.IO/293 ND (OpenScience Framework).
Collapse
Affiliation(s)
- Bas Van Hooren
- Department of Nutrition and Movement Sciences, NUTRIM School of Nutrition and Translational Research in Metabolism, Maastricht University Medical Centre+, Universiteitssingel 50, 6229 ER, Maastricht, The Netherlands.
| | - Ivan Jukic
- Sport Performance Research Institute New Zealand (SPRINZ), Auckland University of Technology, Auckland, New Zealand
- School of Engineering, Computer and Mathematical Sciences, Auckland University of Technology, Auckland, New Zealand
| | - Maartje Cox
- Department of Nutrition and Movement Sciences, NUTRIM School of Nutrition and Translational Research in Metabolism, Maastricht University Medical Centre+, Universiteitssingel 50, 6229 ER, Maastricht, The Netherlands
| | - Koen G Frenken
- Department of Nutrition and Movement Sciences, NUTRIM School of Nutrition and Translational Research in Metabolism, Maastricht University Medical Centre+, Universiteitssingel 50, 6229 ER, Maastricht, The Netherlands
| | - Iker Bautista
- Institute of Sport, Nursing and Allied Health, University of Chichester, Chichester, UK
- Department of Physiotherapy, Catholic University of Valencia, Valencia, Spain
| | - Isabel S Moore
- School of Sport and Health Sciences, Cardiff Metropolitan University, Cardiff, UK
| |
Collapse
|
3
|
Ling DI, Janosky J, Schneider B, Russomano J, Boyle C, Kinderknecht J, Marx RG. A Controlled Trial of the Effects of Neuromuscular Training on Physical Performance in Male and Female High School Athletes. Sports Health 2023; 15:386-396. [PMID: 35499093 PMCID: PMC10170228 DOI: 10.1177/19417381221089917] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
BACKGROUND Neuromuscular training (NMT) has demonstrated efficacy as an intervention to decrease the risk of anterior cruciate ligament injuries and improve sports performance. The effect of this training on the mechanisms that contribute to improved physical performance has not been well defined. HYPOTHESIS Athletes in the NMT group will have better mechanisms of fundamental movements and agility tests that may contribute to improved sports performance. STUDY DESIGN Prospective cohort study. LEVEL OF EVIDENCE Level 2. METHODS Eight high school teams (111 athletes, 53% male, mean age 16 years) participated, with half performing NMT. Physical performance was measured using the dorsaVi ViPerform system, a US Food and Drug Administration-cleared wireless sensor system. Agility was assessed using a timed 3-cone test. Independent sample t tests were used to compare differences between the intervention and control groups. RESULTS Matched pre- and postseason data were collected from 74 athletes after excluding athletes with injury and those lost to follow-up. Significant improvements were observed in the NMT group for loading/landing speed ratios during a single-leg hop test (right lower extremity = -0.19 [-0.37, 0.03], P = 0.03 and left lower extremity = -0.27 [-0.50, -0.03], P = 0.03). The control group had lower ground reaction forces compared with the NMT group (P < 0.02), while significant improvements were found in the NMT group for initial peak acceleration (P < 0.02) and cadence (P = 0.01) during a straight-line acceleration/deceleration test. For the 3-cone agility test, the postseason time decreased compared with preseason in the NMT group, whereas the time for the control group increased (-0.37 s vs 0.14 s, P < 0.00). CONCLUSION The results demonstrate that NMT administered by sports medicine clinicians can significantly improve some physical performance of fundamental movements in high school athletes. CLINICAL RELEVANCE Coaches should be trained to effectively deliver NMT in order to improve sports performance.
Collapse
Affiliation(s)
- Daphne I. Ling
- Sports Medicine Institute, Hospital for
Special Surgery, New York
- Department of Population Health
Sciences, Weill Cornell Medical College, New York
| | - Joseph Janosky
- Sports Safety Program, Sports Medicine
Institute, Hospital for Special Surgery, New York
| | | | | | - Caroline Boyle
- Sports Medicine Institute, Hospital for
Special Surgery, New York
| | | | - Robert G. Marx
- Sports Medicine Institute, Hospital for
Special Surgery, New York
- Department of Orthopedic Surgery, Weill
Cornell Medical College, New York
| |
Collapse
|
4
|
Casado A, Tuimil JL, Iglesias X, Fernández-del-Olmo M, Jiménez-Reyes P, Martín-Acero R, Rodríguez FA. Maximum aerobic speed, maximum oxygen consumption, and running spatiotemporal parameters during an incremental test among middle- and long-distance runners and endurance non-running athletes. PeerJ 2022; 10:e14035. [PMID: 36217384 PMCID: PMC9547581 DOI: 10.7717/peerj.14035] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2022] [Accepted: 08/18/2022] [Indexed: 01/19/2023] Open
Abstract
Background Maximal aerobic speed (MAS) is a useful parameter to assess aerobic capacity and estimate training intensity in middle- and long-distance runners. However, whether middle- and long-distance runners reach different levels of MAS compared to other endurance athletes with similar V̇O2max has not been previously studied. Therefore, we aimed to compare V̇O2max, MAS and spatiotemporal parameters between sub-elite middle- and long-distance runners (n = 6) and endurance non-runners (n = 6). In addition, we aimed to compare the maximal blood lactate concentration [BLa] experienced by participants after conducting these tests. Methods Telemetric portable respiratory gas analysis, contact and flight time, and stride length and rate were measured using a 5-m contact platform during an incremental test at a synthetic athletics track. V̇O2, heart rate, respiratory quotient values in any 15 s average period during the test were measured. [BLa] was analyzed after the test . Running spatiotemporal parameters were recorded at the last two steps of each 400 m lap. A coefficient of variation (%CV) was calculated for each spatiotemporal variable in each participant from 8 km h-1 onwards. Results Whereas runners reported faster MAS (21.0 vs. 18.2 km h-1) than non-runners (p = 0.0001, ES = 3.0), no differences were found for V̇O2max and maximum blood lactate concentration during the running tests (p > 0.05). While significant increases in flight time and stride length and frequency (p < 0.001, 0.52 ≤ η p 2 ≤ 0.8) were observed throughout the tests, decreases in contact time (p < 0.001, η p 2 = 0 . 9 ) were reported. Runners displayed a greater %CV (p = 0.015) in stride length than non-runners. We conclude that middle- and long-distance runners can achieve a faster MAS compared to non-running endurance athletes despite exhibiting a similar V̇O2max. This superior performance may be associated to a greater mechanical efficiency. Overall, runners displayed a greater ability to modify stride length to achieve fast speeds, which may be related to a more mechanically efficient pattern of spatiotemporal parameters than non-runners.
Collapse
Affiliation(s)
- Arturo Casado
- Centre for Sport Studies, Universidad Rey Juan Carlos, Fuenlabrada, Madrid, Spain
| | - José Luis Tuimil
- Faculty of Sports Sciences and Physical Education, Universidad de La Coruña, La Coruña, Galicia, Spain
| | - Xavier Iglesias
- INEFC-Barcelona Sports Science Research Group, Institut Nacional d’Educació Física de Catalunya (INEFC), Universitat de Barcelona, Barcelona, Cataluña, Spain
| | | | - Pedro Jiménez-Reyes
- Centre for Sport Studies, Universidad Rey Juan Carlos, Fuenlabrada, Madrid, Spain
| | - Rafael Martín-Acero
- Faculty of Sports Sciences and Physical Education, Universidad de La Coruña, La Coruña, Galicia, Spain
| | - Ferran A. Rodríguez
- INEFC-Barcelona Sports Science Research Group, Institut Nacional d’Educació Física de Catalunya (INEFC), Universitat de Barcelona, Barcelona, Cataluña, Spain
| |
Collapse
|
5
|
Non-South East Asians have a better running economy and different anthropometrics and biomechanics than South East Asians. Sci Rep 2022; 12:6291. [PMID: 35428794 PMCID: PMC9012817 DOI: 10.1038/s41598-022-10030-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2021] [Accepted: 03/21/2022] [Indexed: 11/09/2022] Open
Abstract
Running biomechanics and ethnicity can influence running economy (RE), which is a critical factor of running performance. Our aim was to compare RE of South East Asian (SEA) and non-South East Asian (non-SEA) runners at several endurance running speeds (10-14 km/h) matched for on-road racing performance and sex. Secondly, we explored anthropometric characteristics and relationships between RE and anthropometric and biomechanical variables. SEA were 6% less economical (p = 0.04) than non-SEA. SEA were lighter and shorter than non-SEA, and had lower body mass indexes and leg lengths (p ≤ 0.01). In terms of biomechanics, a higher prevalence of forefoot strikers in SEA than non-SEA was seen at each speed tested (p ≤ 0.04). Furthermore, SEA had a significantly higher step frequency (p = 0.02), shorter contact time (p = 0.04), smaller footstrike angle (p < 0.001), and less knee extension at toe-off (p = 0.03) than non-SEA. Amongst these variables, only mass was positively correlated to RE for both SEA (12 km/h) and non-SEA (all speeds); step frequency, negatively correlated to RE for both SEA (10 km/h) and non-SEA (12 km/h); and contact time, positively correlated to RE for SEA (12 km/h). Despite the observed anthropometric and biomechanical differences between cohorts, these data were limited in underpinning the observed RE differences at a group level. This exploratory study provides preliminary indications of potential differences between SEA and non-SEA runners warranting further consideration. Altogether, these findings suggest caution when generalizing from non-SEA running studies to SEA runners.
Collapse
|
6
|
Transfer of strength training to running mechanics, energetics, and efficiency. Biol Sport 2022; 39:199-206. [PMID: 35173378 PMCID: PMC8805355 DOI: 10.5114/biolsport.2021.102807] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2020] [Revised: 11/18/2020] [Accepted: 12/13/2020] [Indexed: 11/17/2022] Open
Abstract
To examine the effects of increased strength on mechanical work, the metabolic cost of transport (Cost), and mechanical efficiency (ME) during running. Fourteen physically active men (22.0 ± 2.0 years, 79.3 ± 11.1 kg) were randomized to a strength-training group (SG, n = 7), who participated in a maximal strength training protocol lasting 8 weeks, and a control group (CG, n = 7), which did not perform any training intervention. Metabolic and kinematic data were collected simultaneously while running at a constant speed (2.78 m·s-1). The ME was defined as the ratio between mechanical power (Pmec) and metabolic power (Pmet). The repeated measures two-way ANOVA did not show any significant interaction between groups, despite some large effect sizes (d): internal work (Wint, p = 0.265, d = -1.37), external work (Wext, p = 0.888, d = 0.21), total work (Wtot, p = 0.931, d = -0.17), Pmec (p = 0.917, d = -0.17), step length (SL, p = 0.941, d = 0.24), step frequency (SF, p = 0.814, d = -0.18), contact time (CT, p = 0.120, d = -0.79), aerial time (AT, p = 0.266, d = 1.12), Pmet (p = 0.088, d = 0.85), and ME (p = 0.329, d = 0.54). The exception was a significant decrease in Cost (p = 0.047, d = 0.84) in SG. The paired t-test and Wilcoxon test only detected intragroup differences (pre- vs. post-training) for SG, showing a higher CT (p = 0.041), and a lower Cost (p = 0.003) and Pmet (p = 0.004). The results indicate that improved neuromuscular factors related to strength training may be responsible for the higher metabolic economy of running after 8 weeks of intervention. However, this process was unable to alter running mechanics in order to indicate a significant improvement in ME.
Collapse
|
7
|
Mateus GAS, Assumpção CO, Cabido CET, Veneroso C, Oliveira SFM, Fermino RC, Mortatti A, Lima L, Vilas Boas JP, Banja T. EFFECT OF FATIGUE AND GRADED RUNNING ON KINEMATICS AND KINETICS PARAMETERS IN TRIATHLETES. Int J Sports Med 2022; 43:797-803. [PMID: 35176788 DOI: 10.1055/a-1774-2125] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Abstract
This study aimed to evaluate the effect of cycling-induced fatigue on subsequent running with different ground inclinations on triathletes. Twenty male triathletes ran on a treadmill at individual speeds, on three inclines: level (0%), 7% uphill (7%), and 7% downhill (-7%). Subsequently, the athletes performed an incremental ramp-to-exhaustion (RTE) protocol on an ergometric bicycle until task failure and repeated the running protocol (POST-RTE). During running and cycling was monitored perceived exertion (RPE) and heart rate (HR). Plantar pressure distribution, peak plantar pressure, total foot area, and ground contact time were measured by an in-shoe sensor. Analysis of variance showed that HR (p=0.001; η2=0.63) and RPE (p=0.001; η2=0.82 large effect) were higher in POST-RTE, without interactions between slopes and fatigue. The heel load showed difference between 0% and 7% and 7% and -7% (p=0.001; η2=0.44 large effect) with higher value in -7%. The midfoot showed differences between 0% and -7% with higher value in 0% (p=0.03; η2=0.15 small effect). The contact time showed interactions between fatigue and slopes with a higher value in POST-RTE. Coaches should be aware that training on the uphill and downhill surfaces can alter the plantar load on different foot parts.
Collapse
Affiliation(s)
- Greyce Any Sousa Mateus
- Institute of Physical Education and Sports, Universidade Federal do Ceará, Fortaleza, Brazil
| | | | | | - Cristiano Veneroso
- Departamento de Educação Física, Universidade Federal do Maranhão, Sao Luis, Brazil.,Physiologi department, School of Physical Education, Physiotherapy and Occupational Therapy, Federal University of Minas Gerais, Belo Horizonte, Minas Gerais, Brazil, Belo Horizonte, Brazil
| | | | - Rogério César Fermino
- Programa de Pós-Graduação em Educação Física, Universidade Tecnológica Federal do Paraná, Curitiba, Brazil
| | - Arnaldo Mortatti
- Physical Education, Universidade Federal do Rio Grande do Norte, Natal, Brazil
| | - Leonardo Lima
- Department of Physical Education, UNESP, Rio Claro, Brazil
| | | | - Túlio Banja
- Institute of Physical Education and Sports, Federal University of Ceara, Fortaleza, Brazil
| |
Collapse
|
8
|
Bennett HJ, Haegele JA. Running Biomechanics of Adolescents With Autism Spectrum Disorder. J Biomech Eng 2021; 143:111005. [PMID: 34076239 DOI: 10.1115/1.4051346] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2020] [Indexed: 11/08/2022]
Abstract
Research examining gait biomechanics of persons with autism spectrum disorder (ASD) has grown significantly in recent years and has demonstrated that persons with ASD walk at slower self-selected speeds and with shorter strides, wider step widths, and reduced lower extremity range of motion and moments compared to neurotypical controls. In contrast to walking, running has yet to be examined in persons with ASD. The purpose of this study was to examine lower extremity running biomechanics in adolescents (13-18-year-olds) with ASD and matched (age, sex, and body mass index (BMI)) neurotypical controls. Three-dimensional kinematics and ground reaction forces (GRFs) were recorded while participants ran at two matched speeds: self-selected speed of adolescents with ASD and at 3.0 m/s. Sagittal and frontal plane lower extremity biomechanics and vertical GRF waveforms were compared using two-way analyses of variances (ANOVAs) via statistical parametric mapping (SPM). Adolescents with ASD ran with reduced stride length at self-selected speed (0.29 m) and reduced vertical displacement (2.1 cm), loading-propulsion GRFs (by 14.5%), propulsion plantarflexion moments (18.5%), loading-propulsion hip abduction moments (44.4%), and loading knee abduction moments (69.4%) at both speeds. Running at 3.0 m/s increased sagittal plane hip and knee moments surrounding initial contact (both 10.4%) and frontal plane knee angles during midstance (2.9 deg) and propulsion (2.8 deg) compared to self-selected speeds. Reduced contributions from primarily the ankle plantarflexion but also knee abduction and hip abduction moments likely reduced the vertical GRF and displacement. As differences favored reduced loading, youth with ASD can safely be encouraged to engage in running as a physical activity.
Collapse
Affiliation(s)
- Hunter J Bennett
- Department of Human Movement Sciences, 2016 Student Recreation Center, Old Dominion University, Norfolk, VA 23529
| | - Justin A Haegele
- Department of Human Movement Sciences, Old Dominion University, Norfolk, VA 23529
| |
Collapse
|
9
|
Sundström D, Kurz M, Björklund G. Runners Adapt Different Lower-Limb Movement Patterns With Respect to Different Speeds and Downhill Slopes. Front Sports Act Living 2021; 3:682401. [PMID: 34268493 PMCID: PMC8275652 DOI: 10.3389/fspor.2021.682401] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2021] [Accepted: 06/03/2021] [Indexed: 12/23/2022] Open
Abstract
The aim of this study was to investigate the influence of slope and speed on lower-limb kinematics and energy cost of running. Six well-trained runners (VO2max 72 ± 6 mL·kg−1·min−1) were recruited for the study and performed (1) VO2max and energy cost tests and (2) an experimental running protocol at two speeds, 12 km·h−1 and a speed corresponding to 80% of VO2max (V80, 15.8 ± 1.3 km·h−1) on three different slopes (0°, −5°, and −10°), totaling six 5-min workload conditions. The workload conditions were randomly ordered and performed continuously. The tests lasted 30 min in total. All testing was performed on a large treadmill (3 × 5 m) that offered control over both speed and slope. Three-dimensional kinematic data of the right lower limb were captured during the experimental running protocol using eight infrared cameras with a sampling frequency of 150 Hz. Running kinematics were calculated using a lower body model and inverse kinematics approach. The generic model contained three, one, and two degrees of freedom at the hip, knee, and ankle joints, respectively. Oxygen uptake was measured throughout the experimental protocol. Maximum hip extension and flexion during the stance phase increased due to higher speed (p < 0.01 and p < 0.01, respectively). Knee extension at the touchdown and maximal knee flexion in the stance phase both increased on steeper downhill slopes (both p < 0.05). Ground contact time (GCT) decreased as the speed increased (p < 0.01) but was unaffected by slope (p = 0.73). Runners modified their hip movement pattern in the sagittal plane in response to changes in speed, whereas they altered their knee movement pattern during the touchdown and stance phases in response to changes in slope. While energy cost of running was unaffected by speed alone (p = 0.379), a shift in energy cost was observed for different speeds as the downhill gradient increased (p < 0.001). Energy cost was lower at V80 than 12 km·h−1 on a −5° slope but worse on a −10° slope. This indicates that higher speeds are more efficient on moderate downhill slopes (−5°), while lower speeds are more efficient on steeper downhill slopes (−10°).
Collapse
Affiliation(s)
- David Sundström
- Sports Tech Research Centre, Department of Quality Management and Mechanical Engineering, Mid Sweden University, Östersund, Sweden
| | - Markus Kurz
- Sports Tech Research Centre, Department of Quality Management and Mechanical Engineering, Mid Sweden University, Östersund, Sweden
| | - Glenn Björklund
- Swedish Winter Sport Research Centre, Department of Health Sciences, Mid Sweden University, Östersund, Sweden
| |
Collapse
|
10
|
Validation of Garmin Fenix 3 HR Fitness Tracker Biomechanics and Metabolics (VO2max). ACTA ACUST UNITED AC 2020. [DOI: 10.1123/jmpb.2019-0066] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
The purpose of this study was to determine the validity of the Garmin fēnix® 3 HR fitness tracker. Methods: A total of 34 healthy recreational runners participated in biomechanical or metabolic testing. Biomechanics participants completed three running conditions (flat, incline, and decline) at a self-selected running pace, on an instrumented treadmill while running biomechanics were tracked using a motion capture system. Variables extracted were compared with data collected by the Garmin fēnix 3 HR (worn on the wrist) that was paired with a chest heart rate monitor and a Garmin Foot Pod (worn on the shoe). Metabolic testing involved two separate tests; a graded exercise test to exhaustion utilizing a metabolic cart and treadmill, and a 15-min submaximal outdoor track session while wearing the Garmin. 2 × 3 analysis of variances with post hoc t tests, mean absolute percentage errors, Pearson’s correlation (R), and a t test were used to determine validity. Results: The fēnix kinematics had a mean absolute percentage errors of 9.44%, 0.21%, 26.38%, and 5.77% for stride length, run cadence, vertical oscillation, and ground contact time, respectively. The fēnix overestimated (p < .05) VO2max with a mean absolute percentage error of 8.05% and an R value of .917. Conclusion: The Garmin fēnix 3 HR appears to produce a valid measure of run cadence and ground contact time during running, while it overestimated vertical oscillation in every condition (p < .05) and should be used with caution when determining stride length. The fēnix appears to produce a valid VO2max estimate and may be used when more accurate methods are not available.
Collapse
|
11
|
Liu Q, Mo S, Cheung VCK, Cheung BMF, Wang S, Chan PPK, Malhotra A, Cheung RTH, Chan RHM. Classification of runners' performance levels with concurrent prediction of biomechanical parameters using data from inertial measurement units. J Biomech 2020; 112:110072. [PMID: 33075666 DOI: 10.1016/j.jbiomech.2020.110072] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2020] [Revised: 09/14/2020] [Accepted: 09/23/2020] [Indexed: 11/16/2022]
Abstract
Identification of runner's performance level is critical to coaching, performance enhancement and injury prevention. Machine learning techniques have been developed to measure biomechanical parameters with body-worn inertial measurement unit (IMU) sensors. However, a robust method to classify runners is still unavailable. In this paper, we developed two models to classify running performance and predict biomechanical parameters of 30 subjects. We named the models RunNet-CNN and RunNet-MLP based on their architectures: convolutional neural network (CNN) and multilayer perceptron (MLP), respectively. In addition, we examined two validation approaches, subject-wise (leave-one-subject-out) and record-wise. RunNet-MLP classified runner's performance levels with an overall accuracy of 97.1%. Our results also showed that RunNet-CNN outperformed RunNet-MLP and gradient boosting decision tree in predicting biomechanical parameters. RunNet-CNN showed good agreement (R2 > 0.9) with the ground-truth reference on biomechanical parameters. The prediction accuracy for the record-wise method was better than the subject-wise method regardless of biomechanical parameters or models. Our findings showed the viability of using IMUs to produce reliable prediction of runners' performance levels and biomechanical parameters.
Collapse
Affiliation(s)
- Qi Liu
- Department of Electrical Engineering, City University of Hong Kong, Hong Kong SAR
| | - Shiwei Mo
- Division of Sports Science and Physical Education, Shenzhen University, China; Gait & Motion Analysis Laboratory, Department of Rehabilitation Sciences, The Hong Kong Polytechnic University, Hong Kong SAR
| | - Vincent C K Cheung
- School of Biomedical Sciences, and The Gerald Choa Neuroscience Centre, The Chinese University of Hong Kong, Hong Kong SAR
| | | | - Shuotong Wang
- Gait & Motion Analysis Laboratory, Department of Rehabilitation Sciences, The Hong Kong Polytechnic University, Hong Kong SAR
| | - Peter P K Chan
- Gait & Motion Analysis Laboratory, Department of Rehabilitation Sciences, The Hong Kong Polytechnic University, Hong Kong SAR; School of Biomedical Sciences, and The Gerald Choa Neuroscience Centre, The Chinese University of Hong Kong, Hong Kong SAR
| | - Akash Malhotra
- Gait & Motion Analysis Laboratory, Department of Rehabilitation Sciences, The Hong Kong Polytechnic University, Hong Kong SAR
| | - Roy T H Cheung
- Gait & Motion Analysis Laboratory, Department of Rehabilitation Sciences, The Hong Kong Polytechnic University, Hong Kong SAR; School of Health Sciences, Western Sydney University, Australia.
| | - Rosa H M Chan
- Department of Electrical Engineering, City University of Hong Kong, Hong Kong SAR.
| |
Collapse
|
12
|
Longitudinal Analysis of Plantar Pressures with Wear of a Running Shoe. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2020; 17:ijerph17051707. [PMID: 32151033 PMCID: PMC7084282 DOI: 10.3390/ijerph17051707] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/11/2020] [Revised: 03/02/2020] [Accepted: 03/03/2020] [Indexed: 12/18/2022]
Abstract
Running shoes typically have a lifespan of 300–1000 km, and the plantar pressure pattern during running may change as the shoe wears. So, the aim of this study was to determine the variation of plantar pressures with shoe wear, and the runner’s subjective sensation. Maximun Plantar Pressures (MMP) were measured from 33 male recreational runners at three times during a training season (beginning, 350 km, and 700 km) using the Biofoot/IBV® in-shoe system (Biofoot/IBV®, Valencia, Spain). All the runners wore the same shoes (New Balance® 738, Boston, MA, USA) during this period, and performed similar training. The zones supporting most pressure at all three study times were the medial (inner) column of the foot and the forefoot. There was a significant increase in pressure on the midfoot over the course of the training season (from 387.8 to 590 kPa, p = 0.003). The runners who felt the worst cushioning under the midfoot were those who had the highest peak pressures in that area (p = 0.002). The New Balance® 738 running shoe effectively maintains the plantar pressure pattern after 700 km of use under all the zones studied except the midfoot, probably due to material fatigue or deficits of the specific cushioning systems in that area.
Collapse
|
13
|
Moran MF, Wager JC. Influence of Gait Retraining on Running Economy: A Review and Potential Applications. Strength Cond J 2020. [DOI: 10.1519/ssc.0000000000000511] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
|
14
|
Van Hooren B, Goudsmit J, Restrepo J, Vos S. Real-time feedback by wearables in running: Current approaches, challenges and suggestions for improvements. J Sports Sci 2019; 38:214-230. [PMID: 31795815 DOI: 10.1080/02640414.2019.1690960] [Citation(s) in RCA: 47] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Injuries and lack of motivation are common reasons for discontinuation of running. Real-time feedback from wearables can reduce discontinuation by reducing injury risk and improving performance and motivation. There are however several limitations and challenges with current real-time feedback approaches. We discuss these limitations and challenges and provide a framework to optimise real-time feedback for reducing injury risk and improving performance and motivation. We first discuss the reasons why individuals run and propose that feedback targeted to these reasons can improve motivation and compliance. Secondly, we review the association of running technique and running workload with injuries and performance and we elaborate how real-time feedback on running technique and workload can be applied to reduce injury risk and improve performance and motivation. We also review different feedback modalities and motor learning feedback strategies and their application to real-time feedback. Briefly, the most effective feedback modality and frequency differ between variables and individuals, but a combination of modalities and mixture of real-time and delayed feedback is most effective. Moreover, feedback promoting perceived competence, autonomy and an external focus can improve motivation, learning and performance. Although the focus is on wearables, the challenges and practical applications are also relevant for laboratory-based gait retraining.
Collapse
Affiliation(s)
- Bas Van Hooren
- School of Sport Studies, Fontys University of Applied Sciences, Eindhoven, The Netherlands.,Department of Nutrition and Movement Sciences, NUTRIM School of Nutrition and Translational Research in Metabolism, Maastricht University Medical Centre, Maastricht, The Netherlands
| | - Jos Goudsmit
- School of Sport Studies, Fontys University of Applied Sciences, Eindhoven, The Netherlands.,Department of Industrial Design, Eindhoven University of Technology, Eindhoven, The Netherlands
| | - Juan Restrepo
- Department of Industrial Design, Eindhoven University of Technology, Eindhoven, The Netherlands
| | - Steven Vos
- School of Sport Studies, Fontys University of Applied Sciences, Eindhoven, The Netherlands.,Department of Industrial Design, Eindhoven University of Technology, Eindhoven, The Netherlands
| |
Collapse
|
15
|
Lee EJ, Snyder EM, Lundstrom CJ. The relationships between age and running performance variables in master runners. SPORT SCIENCES FOR HEALTH 2019; 15:543-550. [PMID: 38883203 PMCID: PMC11178332 DOI: 10.1007/s11332-019-00543-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2018] [Accepted: 03/05/2019] [Indexed: 11/26/2022]
Abstract
Purpose Peak aerobic capacity (V̇O2peak) declines with age, but running economy (RE) may not. We evaluated VO2peak and RE in master runners and determined whether age is associated with these measures. Methods In a cross-sectional study, runners completed two running tests within four weeks of a goal race of 10-26.2 miles. Subjects ran for five min at 88% of predicted maximum heart rate, approximating a marathon-intensity effort (MIE), then performed a V̇O2peak test. Running economy in the MIE was measured using oxygen cost with body mass scaled allometrically (alloV̇O2); energy cost (EC), determined using caloric equivalents; and percent of V̇O2peak (%V̇O2peak). Pearson's correlations were used to determine relationships between age and running performance variables. Results Runners (n = 31, 13 females; mean age 54.9 ± 8.4 years) had a mean VO2peak of 52.5 ± 7.9 ml O2 kg-1 min-1. Age was significantly correlated with V̇O2peak (r = - 0.580, p = 0.001) and alloV̇O2 (r = - 0.454, p = 0.034). Age was related to EC in females (r = 0.649, p = 0.042) and MIE V̇O2 in males (r = - 0.600, p = 0.039). Conclusions In this population, age was negatively associated with V̇O2peak and alloV̇O2. Females showed a positive relationship between age and EC, while males had a negative correlation between age and MIE V̇O2. Aerobic capacity declines with age, but there may be sex differences in age-related alterations to submaximal running.
Collapse
Affiliation(s)
- Emma J. Lee
- School of Kinesiology, University of Minnesota, 1900 University Ave. SE, Minneapolis, MN 55455, USA
| | - Eric M. Snyder
- School of Kinesiology, University of Minnesota, 1900 University Ave. SE, Minneapolis, MN 55455, USA
| | - Christopher J. Lundstrom
- School of Kinesiology, University of Minnesota, 1900 University Ave. SE, Minneapolis, MN 55455, USA
| |
Collapse
|
16
|
Weart AN, Szymanek EB, Miller EM, Goss DL. The stability of step rate throughout a 3200 meter run. Gait Posture 2019; 71:284-288. [PMID: 31125836 DOI: 10.1016/j.gaitpost.2019.05.012] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/19/2018] [Revised: 05/01/2019] [Accepted: 05/07/2019] [Indexed: 02/02/2023]
Abstract
Step rate has been studied in controlled laboratory settings due to its association with biomechanical parameters related to running injuries. However, the stability of step rate in a run over ground when speed is not controlled remains unclear. In this observational cohort study, 30 subjects were asked to run 3200 meters (m) over ground at their self-selected pace during an Army Physical Fitness Test. Stationary cameras were placed along the paved course to capture step rate at 800 m, 1200 m, 1800 m, and 2200 m. For analysis of step rate at four different time points, a repeated measures analysis of variance (ANOVA) with a Bonferroni-Holm correction was utilized to determine statistical difference with a significance level set at p < 0.05 (95% confidence intervals). There was a statistically significant (p = 0.04) difference between step rate at two different time points; however, the mean group difference in step rate was approximately 1-2 steps per minute, which is not likely clinically meaningful. There was no difference in average weekly miles trained or performance time in those who demonstrated a change in step rate versus those who maintained a steady step rate. Clinicians and researchers may be able to expect step rate to be consistent from 800 m-2200 m during a 3200 m timed run regardless of the runner's training mileage or performance time. This may be valuable for observing over ground running characteristics when the full course of a run cannot be viewed as it could within a laboratory setting.
Collapse
Affiliation(s)
- Amy N Weart
- Keller Army Community Hospital, West Point, NY, USA.
| | - Eliza B Szymanek
- Madigan Army Medical Center, Joint Base Lewis-McChord, Tacoma, WA, USA.
| | - Erin M Miller
- Keller Army Community Hospital, West Point, NY, USA.
| | - Donald L Goss
- Keller Army Community Hospital, West Point, NY, USA.
| |
Collapse
|
17
|
da Rosa RG, Oliveira HB, Gomeñuka NA, Masiero MPB, da Silva ES, Zanardi APJ, de Carvalho AR, Schons P, Peyré-Tartaruga LA. Landing-Takeoff Asymmetries Applied to Running Mechanics: A New Perspective for Performance. Front Physiol 2019; 10:415. [PMID: 31040793 PMCID: PMC6477028 DOI: 10.3389/fphys.2019.00415] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2018] [Accepted: 03/27/2019] [Indexed: 11/13/2022] Open
Abstract
BACKGROUND Elastic bouncing is a physio-mechanical model that can elucidate running behavior in different situations, including landing and takeoff patterns and the characteristics of the muscle-tendon units during stretch and recoil in running. An increase in running speed improves the body's elastic mechanisms. Although some measures of elastic bouncing are usually carried out, a general description of the elastic mechanism has not been explored in running performance. This study aimed to compare elastic bouncing parameters between the higher- and lower-performing athletes in a 3000 m test. METHODS Thirty-eight endurance runners (men) were divided into two groups based on 3000 m performance: the high-performance group (Phigh; n = 19; age: 29 ± 5 years; mass: 72.9 ± 10 kg; stature: 177 ± 8 cm; 3000time: 656 ± 32 s) and the low-performance group (Plow; n = 19; age: 32 ± 6 years; mass: 73.9 ± 7 kg; stature: 175 ± 5 cm; 3000time: 751 ± 29 s). They performed three tests on different days: (i) 3000 m on a track; (ii) incremental running test; and (iii) a running biomechanical test on a treadmill at 13 different speeds from 8 to 20 km h-1. Performance was evaluated using the race time of the 3000 m test. The biomechanics variables included effective contact time (t ce), aerial time (t ae), positive work time (t push), negative work time (t break), step frequency (f step), and elastic system frequency (f sist), vertical displacement (S v) in t ce and t ae (S ce and S ae), vertical force, and vertical stiffness were evaluated in a biomechanical submaximal test on treadmill. RESULTS The t ae, f sist, vertical force and stiffness were higher (p < 0.05) and t ce and f step were lower (p < 0.05) in Phigh, with no differences between groups in t push and t break. CONCLUSION The elastic bouncing was optimized in runners of the best performance level, demonstrating a better use of elastic components.
Collapse
Affiliation(s)
- Rodrigo Gomes da Rosa
- Laboratório de Pesquisa do Exercício, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil
| | - Henrique Bianchi Oliveira
- Laboratório de Pesquisa do Exercício, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil
| | - Natalia Andrea Gomeñuka
- Departamento de Investigación de la Facultad de Ciencias de la Salud, Universidad Católica de las Misiones (UCAMI), Posadas, Argentina
| | | | - Edson Soares da Silva
- Laboratório de Pesquisa do Exercício, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil
| | - Ana Paula Janner Zanardi
- Laboratório de Pesquisa do Exercício, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil
| | | | - Pedro Schons
- Laboratório de Pesquisa do Exercício, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil
| | | |
Collapse
|
18
|
Aubry RL, Power GA, Burr JF. An Assessment of Running Power as a Training Metric for Elite and Recreational Runners. J Strength Cond Res 2018; 32:2258-2264. [PMID: 29912073 DOI: 10.1519/jsc.0000000000002650] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Aubry, RL, Power, GA, and Burr, JF. An assessment of running power as a training metric for elite and recreational runners. J Strength Cond Res 32(8): 2258-2264, 2018-Power, as a testing and training metric to quantify effort, is well accepted in cycling, but is not commonly used in running to quantify effort or performance. This study sought to investigate a novel training tool, the Stryd Running Power Meter, and the applicability of running power (and its individually calculated run mechanics) to be a useful surrogate of metabolic demand (V[Combining Dot Above]O2), across different running surfaces, within different caliber runners. Recreational (n = 13) and elite (n = 11) runners completed a test assessing V[Combining Dot Above]O2 at 3 different paces, while wearing a Stryd Power Meter on both an indoor treadmill and an outdoor track, to investigate relationships between estimated running power and metabolic demand. A weak but significant relationship was found between running power and V[Combining Dot Above]O2 considering all participants as a homogenous group (r = 0.29); however, when assessing each population individually, no significant relationship was found. Examination of the individual mechanical components of power revealed that a correlative decrease in V[Combining Dot Above]O2 representing improved efficiency was associated with decreased ground contact time (r = 0.56), vertical oscillation (r = 0.46), and cadence (r = 0.37) on the treadmill in the recreational group only. Although metabolic demand differed significantly between surfaces at most speeds, run power did not accurately reflect differences in metabolic cost between the 2 surfaces. Running power, calculated via the Stryd Power Meter, is not sufficiently accurate as a surrogate of metabolic demand, particularly in the elite population. However, in a recreational population, this training tool could be useful for feedback on several running dynamics known to influence running economy.
Collapse
Affiliation(s)
- Rachel L Aubry
- Human Health and Nutritional Sciences, Human Performance and Health Research Laboratory, Human Health and Nutritional Sciences, University of Guelph, Ontario, Canada
| | - Geoff A Power
- Human Health and Nutritional Sciences, Neuromechanical Performance Research Laboratory, Human Health and Nutritional Sciences, University of Guelph, Ontario, Canada
| | - Jamie F Burr
- Human Health and Nutritional Sciences, Human Performance and Health Research Laboratory, Human Health and Nutritional Sciences, University of Guelph, Ontario, Canada
| |
Collapse
|
19
|
Couture GA, Simperingham KD, Cronin JB, Lorimer AV, Kilding AE, Macadam P. Effects of upper and lower body wearable resistance on spatio-temporal and kinetic parameters during running. Sports Biomech 2018; 19:633-651. [PMID: 30325270 DOI: 10.1080/14763141.2018.1508490] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Abstract
Wearable resistance training involves added load attached directly to the body during sporting movements. The effects of load position during running are not yet fully established. Therefore, the purpose of this research was to determine spatio-temporal and kinetic characteristics during submaximal running using upper, lower and whole-body wearable resistance (1-10% body mass (BM)). Twelve trained male runners completed eight 2-min treadmill running bouts at 3.9 m/s with and without wearable resistance. The first and last bouts were unloaded, while the middle 6 were randomised wearable resistance conditions: upper body (UB) 5% BM, lower body (LB) 1%, 3%, 5% BM and whole body (WB) 5%, 10% BM. Wearable resistance of 1-10% BM resulted in a significant increase in heart rate (5.40-8.84%), but minimal impact on spatio-temporal variables. Loads of 5% BM and greater caused changes in vertical stiffness, vertical and horizontal force, and impulse. Functional and effective propulsive force (2.95%, 2.88%) and impulse (3.40%, 3.38%) were significantly (p < 0.05) greater with LB5% than UB5%. Wearable resistance may be used to increase muscular kinetics during running without negatively impacting spatio-temporal variables. The application of these findings will vary depending on athlete goals. Future longitudinal studies are required to validate training contentions.
Collapse
Affiliation(s)
- Grace A Couture
- Sports Performance Research Institute New Zealand, Auckland University of Technology , Auckland, New Zealand.,Department of Movement Science, Grand Valley State University , Allendale, MI, USA
| | - Kim D Simperingham
- Sports Performance Research Institute New Zealand, Auckland University of Technology , Auckland, New Zealand
| | - John B Cronin
- Sports Performance Research Institute New Zealand, Auckland University of Technology , Auckland, New Zealand.,School of Exercise and Biomedical Health Science, Edith Cowan University , Perth, Australia
| | - Anna V Lorimer
- Sports Performance Research Institute New Zealand, Auckland University of Technology , Auckland, New Zealand
| | - Andrew E Kilding
- Sports Performance Research Institute New Zealand, Auckland University of Technology , Auckland, New Zealand
| | - Paul Macadam
- Sports Performance Research Institute New Zealand, Auckland University of Technology , Auckland, New Zealand
| |
Collapse
|
20
|
Napier C, MacLean CL, Maurer J, Taunton JE, Hunt MA. Kinetic risk factors of running-related injuries in female recreational runners. Scand J Med Sci Sports 2018; 28:2164-2172. [DOI: 10.1111/sms.13228] [Citation(s) in RCA: 61] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/23/2018] [Indexed: 11/30/2022]
Affiliation(s)
- C. Napier
- Department of Physical Therapy; Faculty of Medicine; University of British Columbia; Vancouver BC Canada
- Fortius Lab; Fortius Institute; Burnaby BC Canada
| | - C. L. MacLean
- Department of Physical Therapy; Faculty of Medicine; University of British Columbia; Vancouver BC Canada
- Fortius Lab; Fortius Institute; Burnaby BC Canada
| | - J. Maurer
- Fortius Lab; Fortius Institute; Burnaby BC Canada
| | - J. E. Taunton
- Fortius Lab; Fortius Institute; Burnaby BC Canada
- Division of Sports Medicine; Department of Family Practice; Faculty of Medicine; University of British Columbia; Vancouver BC Canada
| | - M. A. Hunt
- Department of Physical Therapy; Faculty of Medicine; University of British Columbia; Vancouver BC Canada
| |
Collapse
|
21
|
Lopezosa-Reca E, Gijon-Nogueron G, Garcia-Paya I, Ortega-Avila AB. Does the type of sport practised influence foot posture and knee angle? Differences between footballers and swimmers. Res Sports Med 2018; 26:345-353. [DOI: 10.1080/15438627.2018.1447470] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Affiliation(s)
- Eva Lopezosa-Reca
- Department of Nursing and Podiatry, University of Malaga, Malaga, Spain
| | | | - Irene Garcia-Paya
- Department of Nursing and Podiatry, University of Malaga, Malaga, Spain
| | | |
Collapse
|
22
|
Gómez-Molina J, Ogueta-Alday A, Stickley C, Cámara J, Cabrejas-Ugartondo J, García-López J. Differences in Spatiotemporal Parameters Between Trained Runners and Untrained Participants. J Strength Cond Res 2018; 31:2169-2175. [PMID: 28731978 DOI: 10.1519/jsc.0000000000001679] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Gómez-Molina, J, Ogueta-Alday, A, Stickley, C, Tobalina, JC, Cabrejas-Ugartondo, J, and García-López, J. Differences in spatiotemporal parameters between trained runners and untrained participants. J Strength Cond Res 31(8): 2169-2175, 2017-The aim of this study was to compare the spatiotemporal parameters of trained runners and untrained participants with the same foot strike pattern (rearfoot) during running at controlled speeds. Twenty-one participants were classified in 2 groups according to their training experience: Trained (n = 10, amateur runners with long distance training experience) and Untrained (n = 11, healthy untrained participants). Anthropometric variables were recorded, and the participants performed both a submaximal (between 9 and 15 km·h) and a graded exercise running test (from 6 km·h until exhaustion) on a treadmill. Physiological (V[Combining Dot Above]O2max, heart rate, running economy [RE], peak speed …) and biomechanical variables (contact and flight times, step rate, and length) were simultaneously registered. Trained runners showed higher step rate and shorter step length than the Untrained group at the same running speeds (between 4 and 7%, p ≤ 0.05) and at the same physiological intensities (between 7 and 11%, p ≤ 0.05). However, there were no differences in contact and flight times between groups. Significant differences (p ≤ 0.05) and large effect sizes (Cohen's d) between groups were found for body mass, sum of 6 skinfolds, V[Combining Dot Above]O2max, peak speed, and ventilatory threshold and respiratory compensation threshold speeds. The Trained group also showed a ∼7% better RE (ml·kg·km) than the Untrained group. In conclusion, adopting higher step rate and shorter step length may be an adaptive mechanism of the Trained group to reduce injury risk and possibly improve RE. However, contact and flight times were consistent regardless of training level.
Collapse
Affiliation(s)
- Josué Gómez-Molina
- 1Faculty of Education and Sport, University of the Basque Country, UPV/EHU, Vitoria-Gasteiz, Spain; 2Department of Kinesiology and Rehabilitation Science, College of Education, University of Hawaii at Manoa, Honolulu, Hawaii; 3Departament of Internal Medicine, Regional Hospital Santiago Apostol, SACYL, Miranda de Ebro, Spain; and 4Department of Physical Education and Sports, Institute of Biomedicine (IBIOMED), University of León, León, Spain
| | | | | | | | | | | |
Collapse
|
23
|
Ogueta-Alday A, Morante JC, Gómez-Molina J, García-López J. Similarities and differences among half-marathon runners according to their performance level. PLoS One 2018; 13:e0191688. [PMID: 29364940 PMCID: PMC5783408 DOI: 10.1371/journal.pone.0191688] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2017] [Accepted: 01/09/2018] [Indexed: 11/20/2022] Open
Abstract
This study aimed to identify the similarities and differences among half-marathon runners in relation to their performance level. Forty-eight male runners were classified into 4 groups according to their performance level in a half-marathon (min): Group 1 (n = 11, < 70 min), Group 2 (n = 13, < 80 min), Group 3 (n = 13, < 90 min), Group 4 (n = 11, < 105 min). In two separate sessions, training-related, anthropometric, physiological, foot strike pattern and spatio-temporal variables were recorded. Significant differences (p<0.05) between groups (ES = 0.55–3.16) and correlations with performance were obtained (r = 0.34–0.92) in training-related (experience and running distance per week), anthropometric (mass, body mass index and sum of 6 skinfolds), physiological (VO2max, RCT and running economy), foot strike pattern and spatio-temporal variables (contact time, step rate and length). At standardized submaximal speeds (11, 13 and 15 km·h-1), no significant differences between groups were observed in step rate and length, neither in contact time when foot strike pattern was taken into account. In conclusion, apart from training-related, anthropometric and physiological variables, foot strike pattern and step length were the only biomechanical variables sensitive to half-marathon performance, which are essential to achieve high running speeds. However, when foot strike pattern and running speeds were controlled (submaximal test), the spatio-temporal variables were similar. This indicates that foot strike pattern and running speed are responsible for spatio-temporal differences among runners of different performance level.
Collapse
Affiliation(s)
- Ana Ogueta-Alday
- Department of Physical Education and Sports, Institute of Biomedicine (IBIOMED), Faculty of Physical Activity and Sports Sciences (FCAFD), University of León, León, Spain
- * E-mail:
| | - Juan Carlos Morante
- Department of Physical Education and Sports, Institute of Biomedicine (IBIOMED), Faculty of Physical Activity and Sports Sciences (FCAFD), University of León, León, Spain
| | - Josué Gómez-Molina
- Department of Physical Education and Sports, Faculty of Education and Sport, University of the Basque Country, UPV/EHU, Spain
| | - Juan García-López
- Department of Physical Education and Sports, Institute of Biomedicine (IBIOMED), Faculty of Physical Activity and Sports Sciences (FCAFD), University of León, León, Spain
- High Sport Performance Centre of León (CAR-León), Spanish Council of Sports (CSD), León, Spain
| |
Collapse
|
24
|
Moore IS. Is There an Economical Running Technique? A Review of Modifiable Biomechanical Factors Affecting Running Economy. Sports Med 2017; 46:793-807. [PMID: 26816209 PMCID: PMC4887549 DOI: 10.1007/s40279-016-0474-4] [Citation(s) in RCA: 194] [Impact Index Per Article: 27.7] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Running economy (RE) has a strong relationship with running performance, and modifiable running biomechanics are a determining factor of RE. The purposes of this review were to (1) examine the intrinsic and extrinsic modifiable biomechanical factors affecting RE; (2) assess training-induced changes in RE and running biomechanics; (3) evaluate whether an economical running technique can be recommended and; (4) discuss potential areas for future research. Based on current evidence, the intrinsic factors that appeared beneficial for RE were using a preferred stride length range, which allows for stride length deviations up to 3 % shorter than preferred stride length; lower vertical oscillation; greater leg stiffness; low lower limb moment of inertia; less leg extension at toe-off; larger stride angles; alignment of the ground reaction force and leg axis during propulsion; maintaining arm swing; low thigh antagonist–agonist muscular coactivation; and low activation of lower limb muscles during propulsion. Extrinsic factors associated with a better RE were a firm, compliant shoe–surface interaction and being barefoot or wearing lightweight shoes. Several other modifiable biomechanical factors presented inconsistent relationships with RE. Running biomechanics during ground contact appeared to play an important role, specifically those during propulsion. Therefore, this phase has the strongest direct links with RE. Recurring methodological problems exist within the literature, such as cross-comparisons, assessing variables in isolation, and acute to short-term interventions. Therefore, recommending a general economical running technique should be approached with caution. Future work should focus on interdisciplinary longitudinal investigations combining RE, kinematics, kinetics, and neuromuscular and anatomical aspects, as well as applying a synergistic approach to understanding the role of kinetics.
Collapse
Affiliation(s)
- Isabel S Moore
- Cardiff School of Sport, Cardiff Metropolitan University, Cardiff, CF23 6XD, Wales, UK.
| |
Collapse
|
25
|
Beck ON, Taboga P, Grabowski AM. Reduced prosthetic stiffness lowers the metabolic cost of running for athletes with bilateral transtibial amputations. J Appl Physiol (1985) 2017; 122:976-984. [PMID: 28104752 DOI: 10.1152/japplphysiol.00587.2016] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2016] [Revised: 12/15/2016] [Accepted: 01/12/2017] [Indexed: 11/22/2022] Open
Abstract
Inspired by the springlike action of biological legs, running-specific prostheses are designed to enable athletes with lower-limb amputations to run. However, manufacturer’s recommendations for prosthetic stiffness and height may not optimize running performance. Therefore, we investigated the effects of using different prosthetic configurations on the metabolic cost and biomechanics of running. Five athletes with bilateral transtibial amputations each performed 15 trials on a force-measuring treadmill at 2.5 or 3.0 m/s. Athletes ran using each of 3 different prosthetic models (Freedom Innovations Catapult FX6, Össur Flex-Run, and Ottobock 1E90 Sprinter) with 5 combinations of stiffness categories (manufacturer’s recommended and ± 1) and heights (International Paralympic Committee’s maximum competition height and ± 2 cm) while we measured metabolic rates and ground reaction forces. Overall, prosthetic stiffness [fixed effect (β) = 0.036; P = 0.008] but not height ( P ≥ 0.089) affected the net metabolic cost of transport; less stiff prostheses reduced metabolic cost. While controlling for prosthetic stiffness (in kilonewtons per meter), using the Flex-Run (β = −0.139; P = 0.044) and 1E90 Sprinter prostheses (β = −0.176; P = 0.009) reduced net metabolic costs by 4.3–4.9% compared with using the Catapult prostheses. The metabolic cost of running improved when athletes used prosthetic configurations that decreased peak horizontal braking ground reaction forces (β = 2.786; P = 0.001), stride frequencies (β = 0.911; P < 0.001), and leg stiffness values (β = 0.053; P = 0.009). Remarkably, athletes did not maintain overall leg stiffness across prosthetic stiffness conditions. Rather, the in-series prosthetic stiffness governed overall leg stiffness. The metabolic cost of running in athletes with bilateral transtibial amputations is influenced by prosthetic model and stiffness but not height. NEW & NOTEWORTHY We measured the metabolic rates and biomechanics of five athletes with bilateral transtibial amputations while running with different prosthetic configurations. The metabolic cost of running for these athletes is minimized by using an optimal prosthetic model and reducing prosthetic stiffness. The metabolic cost of running was independent of prosthetic height, suggesting that longer legs are not advantageous for distance running. Moreover, the in-series prosthetic stiffness governs the leg stiffness of athletes with bilateral leg amputations.
Collapse
Affiliation(s)
- Owen N. Beck
- Department of Integrative Physiology, University of Colorado, Boulder, Colorado; and
| | - Paolo Taboga
- Department of Integrative Physiology, University of Colorado, Boulder, Colorado; and
| | - Alena M. Grabowski
- Department of Integrative Physiology, University of Colorado, Boulder, Colorado; and
- Department of Veterans Affairs, Eastern Colorado Healthcare System, Denver, Colorado
| |
Collapse
|
26
|
Beck ON, Taboga P, Grabowski AM. Prosthetic model, but not stiffness or height, affects the metabolic cost of running for athletes with unilateral transtibial amputations. J Appl Physiol (1985) 2017; 123:38-48. [PMID: 28360121 DOI: 10.1152/japplphysiol.00896.2016] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2016] [Revised: 03/27/2017] [Accepted: 03/27/2017] [Indexed: 11/22/2022] Open
Abstract
Running-specific prostheses enable athletes with lower limb amputations to run by emulating the spring-like function of biological legs. Current prosthetic stiffness and height recommendations aim to mitigate kinematic asymmetries for athletes with unilateral transtibial amputations. However, it is unclear how different prosthetic configurations influence the biomechanics and metabolic cost of running. Consequently, we investigated how prosthetic model, stiffness, and height affect the biomechanics and metabolic cost of running. Ten athletes with unilateral transtibial amputations each performed 15 running trials at 2.5 or 3.0 m/s while we measured ground reaction forces and metabolic rates. Athletes ran using three different prosthetic models with five different stiffness category and height combinations per model. Use of an Ottobock 1E90 Sprinter prosthesis reduced metabolic cost by 4.3 and 3.4% compared with use of Freedom Innovations Catapult [fixed effect (β) = -0.177; P < 0.001] and Össur Flex-Run (β = -0.139; P = 0.002) prostheses, respectively. Neither prosthetic stiffness (P ≥ 0.180) nor height (P = 0.062) affected the metabolic cost of running. The metabolic cost of running was related to lower peak (β = 0.649; P = 0.001) and stance average (β = 0.772; P = 0.018) vertical ground reaction forces, prolonged ground contact times (β = -4.349; P = 0.012), and decreased leg stiffness (β = 0.071; P < 0.001) averaged from both legs. Metabolic cost was reduced with more symmetric peak vertical ground reaction forces (β = 0.007; P = 0.003) but was unrelated to stride kinematic symmetry (P ≥ 0.636). Therefore, prosthetic recommendations based on symmetric stride kinematics do not necessarily minimize the metabolic cost of running. Instead, an optimal prosthetic model, which improves overall biomechanics, minimizes the metabolic cost of running for athletes with unilateral transtibial amputations.NEW & NOTEWORTHY The metabolic cost of running for athletes with unilateral transtibial amputations depends on prosthetic model and is associated with lower peak and stance average vertical ground reaction forces, longer contact times, and reduced leg stiffness. Metabolic cost is unrelated to prosthetic stiffness, height, and stride kinematic symmetry. Unlike nonamputees who decrease leg stiffness with increased in-series surface stiffness, biological limb stiffness for athletes with unilateral transtibial amputations is positively correlated with increased in-series (prosthetic) stiffness.
Collapse
Affiliation(s)
- Owen N Beck
- Department of Integrative Physiology, University of Colorado, Boulder, Colorado; and
| | - Paolo Taboga
- Department of Integrative Physiology, University of Colorado, Boulder, Colorado; and
| | - Alena M Grabowski
- Department of Integrative Physiology, University of Colorado, Boulder, Colorado; and.,Department of Veterans Affairs, Eastern Colorado Healthcare System, Denver, Colorado
| |
Collapse
|
27
|
Hoff J, Støren Ø, Finstad A, Wang E, Helgerud J. Increased Blood Lactate Level Deteriorates Running Economy in World Class Endurance Athletes. J Strength Cond Res 2016; 30:1373-8. [DOI: 10.1519/jsc.0000000000001349] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
|
28
|
Fuller JT, Thewlis D, Tsiros MD, Brown NAT, Buckley JD. Effects of a minimalist shoe on running economy and 5-km running performance. J Sports Sci 2016; 34:1740-5. [PMID: 27328725 DOI: 10.1080/02640414.2015.1136071] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
The purpose of this study was to determine if minimalist shoes improve time trial performance of trained distance runners and if changes in running economy, shoe mass, stride length, stride rate and footfall pattern were related to any difference in performance. Twenty-six trained runners performed three 6-min sub-maximal treadmill runs at 11, 13 and 15 km·h(-1) in minimalist and conventional shoes while running economy, stride length, stride rate and footfall pattern were assessed. They then performed a 5-km time trial. In the minimalist shoe, runners completed the trial in less time (effect size 0.20 ± 0.12), were more economical during sub-maximal running (effect size 0.33 ± 0.14) and decreased stride length (effect size 0.22 ± 0.10) and increased stride rate (effect size 0.22 ± 0.11). All but one runner ran with a rearfoot footfall in the minimalist shoe. Improvements in time trial performance were associated with improvements in running economy at 15 km·h(-1) (r = 0.58), with 79% of the improved economy accounted for by reduced shoe mass (P < 0.05). The results suggest that running in minimalist shoes improves running economy and 5-km running performance.
Collapse
Affiliation(s)
- Joel T Fuller
- a Alliance for Research in Exercise, Nutrition and Activity (ARENA), Sansom Institute for Health Research , University of South Australia , Adelaide , SA , Australia
| | - Dominic Thewlis
- a Alliance for Research in Exercise, Nutrition and Activity (ARENA), Sansom Institute for Health Research , University of South Australia , Adelaide , SA , Australia
| | - Margarita D Tsiros
- a Alliance for Research in Exercise, Nutrition and Activity (ARENA), Sansom Institute for Health Research , University of South Australia , Adelaide , SA , Australia
| | | | - Jonathan D Buckley
- a Alliance for Research in Exercise, Nutrition and Activity (ARENA), Sansom Institute for Health Research , University of South Australia , Adelaide , SA , Australia
| |
Collapse
|
29
|
GOJANOVIC BORIS, SHULTZ REBECCA, FEIHL FRANCOIS, MATHESON GORDON. Overspeed HIIT in Lower-Body Positive Pressure Treadmill Improves Running Performance. Med Sci Sports Exerc 2015; 47:2571-8. [DOI: 10.1249/mss.0000000000000707] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
|
30
|
Moore IS, Jones AM, Dixon SJ. Reduced oxygen cost of running is related to alignment of the resultant GRF and leg axis vector: A pilot study. Scand J Med Sci Sports 2015; 26:809-15. [PMID: 26148145 DOI: 10.1111/sms.12514] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/26/2015] [Indexed: 11/27/2022]
Abstract
This pilot study investigated whether a 10-week running program (10wkRP), which reduced the oxygen cost of running, affected resultant ground reaction force (GRF), leg axis alignment, joint moment characteristics, and gear ratios. Ten novice, female runners completed a 10wkRP. Running kinematics and kinetics, in addition to oxygen consumption ( V ˙ O 2 ) during steady-state running, were recorded pre- and post-10wkRP. V ˙ O 2 decreased (8%) from pre-10wkRP to post-10wkRP. There was a better alignment of the resultant GRF and leg axis at peak propulsion post-10wkRP compared with pre-10wkRP (10.8 ± 4.9 vs 1.6 ± 1.2°), as the resultant GRF vector was applied 7 ± 0.6° (P = 0.008) more horizontally. There were shorter external ankle moment arms (24%) and smaller knee extensor moments (23%) at peak braking post-10wkRP. The change in V ˙ O 2 was associated with the change in alignment of the resultant GRF and leg axis (rs = 0.88, P = 0.003). As runners became more economical, they exhibited a more aligned resultant GRF vector and leg axis at peak propulsion. This appears to be a self-optimization strategy that may improve performance. Additionally, changes to external ankle moment arms indicated beneficial low gear ratios were achieved at the time of peak braking force.
Collapse
Affiliation(s)
- I S Moore
- Sports injury Research Group, Cardiff School of Sport, Cardiff Metropolitan University, Cardiff, UK
| | - A M Jones
- Bioenergetics and Human Performance Research Group, Sport and Health Sciences, University of Exeter, Exeter, UK
| | - S J Dixon
- Bioenergetics and Human Performance Research Group, Sport and Health Sciences, University of Exeter, Exeter, UK
| |
Collapse
|
31
|
Azevedo AP, Mezêncio B, Valvassori R, Anjos FO, Barbanti VJ, Amadio AC, Serrão JC. Usage of Running Drills in an Interval Training Program. J Strength Cond Res 2015; 29:1796-802. [DOI: 10.1519/jsc.0000000000000831] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
|
32
|
Running economy: measurement, norms, and determining factors. SPORTS MEDICINE-OPEN 2015; 1:8. [PMID: 27747844 PMCID: PMC4555089 DOI: 10.1186/s40798-015-0007-y] [Citation(s) in RCA: 182] [Impact Index Per Article: 20.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/28/2014] [Accepted: 12/16/2014] [Indexed: 12/03/2022]
Abstract
Running economy (RE) is considered an important physiological measure for endurance athletes, especially distance runners. This review considers 1) how RE is defined and measured and 2) physiological and biomechanical factors that determine or influence RE. It is difficult to accurately ascertain what is good, average, and poor RE between athletes and studies due to variation in protocols, gas-analysis systems, and data averaging techniques. However, representative RE values for different caliber of male and female runners can be identified from existing literature with mostly clear delineations in oxygen uptake across a range of speeds in moderately and highly trained and elite runners. Despite being simple to measure and acceptably reliable, it is evident that RE is a complex, multifactorial concept that reflects the integrated composite of a variety of metabolic, cardiorespiratory, biomechanical and neuromuscular characteristics that are unique to the individual. Metabolic efficiency refers to the utilization of available energy to facilitate optimal performance, whereas cardiopulmonary efficiency refers to a reduced work output for the processes related to oxygen transport and utilization. Biomechanical and neuromuscular characteristics refer to the interaction between the neural and musculoskeletal systems and their ability to convert power output into translocation and therefore performance. Of the numerous metabolic, cardiopulmonary, biomechanical and neuromuscular characteristics contributing to RE, many of these are able to adapt through training or other interventions resulting in improved RE.
Collapse
|
33
|
Støren Ø, Ulevåg K, Larsen MH, Støa EM, Helgerud J. Physiological determinants of the cycling time trial. J Strength Cond Res 2014; 27:2366-73. [PMID: 23238091 DOI: 10.1519/jsc.0b013e31827f5427] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
The purpose of this study was to examine the physiological determinants of endurance cycling time trial (TT) performance in a heterogeneous group of competitive male road cyclists. About 15 male cyclists who had all competed in cycling the preceding season were tested for the anthropometric variables height, body weight, leg length, ankle circumference, and body fat percentage. They were also tested for maximal oxygen consumption (VO2max), lactate threshold (LT), metabolic cost of cycling (CC), peak power output and average power output during a 30-second Wingate test, 1 repetition maximum and peak power in half squats, and a TT test on an ergometer. Heart rate and cadence (rounds per minute, RPM) were continuously measured during all cycle tests. Pearson Bivariate correlation tests and single linear regression tests were performed to obtain correlation coefficients (r), effect size (F), standard error of estimate (SEE), and 95% confidence interval. The single variable that correlated best with TT performance was power output at LT (r = 0.86, p < 0.01). Standard error of estimate was 7.5%. Lactate threshold expressed in %VO2max did not correlate significantly with TT performance. An equation representing both aerobic and anaerobic endurance capacity TT(w) = 0.95 ([VO2max/CC] TT%VO2max) + 0.05 (Wingate average) correlated strongly with TT laboratory performance (r = 0.93, p < 0.01, SEE = 5.7%). None of the strength, power, or anthropometric variables correlated significantly with TT laboratory performance.
Collapse
Affiliation(s)
- Øyvind Støren
- Department of Sport and Outdoor Life Studies, Telemark University College, Bø, Telemark, Norway.
| | | | | | | | | |
Collapse
|
34
|
Di Michele R, Merni F. The concurrent effects of strike pattern and ground-contact time on running economy. J Sci Med Sport 2013; 17:414-8. [PMID: 23806876 DOI: 10.1016/j.jsams.2013.05.012] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2012] [Revised: 04/05/2013] [Accepted: 05/23/2013] [Indexed: 11/18/2022]
Abstract
OBJECTIVES Running economy is a key determinant of endurance performance, and understanding the biomechanical factors that affect it is of great theoretical and applied interest. This study aimed to analyse how the ground-contact time and strike pattern used by competitive runners concurrently affect running economy. DESIGN Cross-sectional. METHODS Fourteen sub-elite male competitive distance runners completed a 6-min submaximal running trial at 14kmh(-1) on an outdoor track using their habitual strike pattern (n=7 rearfoot strikers: average age, 25.3 years old (SD=2.4); average weight, 64.7kg (SD=5.6); average height, 175.3cm (SD=5.2); n=7 midfoot strikers: average age, 25.0 years old (SD=2.8); average weight, 69.6kg (SD=4.0); average height, 180.1cm (SD=5.1). During the run, the oxygen uptake and ground-contact time were measured. RESULTS Midfoot strikers showed a significantly shorter (p=0.015) mean contact time (0.228s (SD=0.009)) compared with rearfoot strikers (0.242s (SD=0.010)). Conversely, there was no significant difference (p>0.05) between the groups with respect to mean oxygen uptake (midfoot strikers: 48.4mlmin(-1)kg(-1) (SD=5.3); rearfoot strikers: 49.8mlmin(-1)kg(-1) (SD=6.4)). Linear modelling analysis showed that the effect of contact time on running economy was very similar in the two groups, with a 1ms longer contact time involving an approximately 0.51mlmin(-1)kg(-1) lower oxygen uptake. In contrast, when controlling for contact time, midfoot striking involved an approximately 8.7mlmin(-1)kg(-1) lower oxygen uptake compared with rearfoot striking. CONCLUSIONS When adjusting the foot-ground contact biomechanics of a runner with the aim of maximising running economy, a trade-off between a midfoot strike and a long contact time must be pursued.
Collapse
Affiliation(s)
- Rocco Di Michele
- Department of Biomedical and Neuromotor Sciences, School of Pharmacy, Biotechnology and Sport Science, University of Bologna, Italy.
| | - Franco Merni
- Department of Biomedical and Neuromotor Sciences, School of Pharmacy, Biotechnology and Sport Science, University of Bologna, Italy
| |
Collapse
|
35
|
Ogueta-Alday A, Morante JC, Rodríguez-Marroyo JA, García-López J. Validation of a New Method to Measure Contact and Flight Times During Treadmill Running. J Strength Cond Res 2013; 27:1455-62. [DOI: 10.1519/jsc.0b013e318269f760] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
|
36
|
Halvorsen K, Eriksson M, Gullstrand L. Acute effects of reducing vertical displacement and step frequency on running economy. J Strength Cond Res 2012; 26:2065-70. [PMID: 22027846 DOI: 10.1519/jsc.0b013e318239f87f] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
This work studies the immediate effects of altering the vertical displacement of the center of mass (VD) and step frequency (SF) on the metabolic cost of level treadmill running at 16 km · h(-1) on 16 male runners. Alterations of VD, SF, and the product VD × SF was induced using a novel feedback system, which presents target and current values to the runner by visual or auditory display. Target values were set to 5 and 10% reductions from individual baseline values. The results were expressed as relative changes from baseline values. Alterations led to an increase in metabolic cost in most cases, measured as V(O2) uptake per minute and kilogram of body mass. Correlations were weak. Still, linear multiple regression revealed a positive coefficient (0.28) for the relationship between VD × SF and V(O2). Separate rank correlation tests showed negative correlation (τ = -0.19) between SF and V(O2) and positive correlation (τ = 0.16) between VD and V(O2). There is a coupling between VD and SF caused by the mechanics of running; hence, isolated reduction of either factor was hard to achieve. The linear model also showed a negative coefficient for the relationship between the height of the center of mass above the ground (CoMh) and V(O2). The effect size was small (multiple R(2) 0.07 and 0.12). Still the results indicate that reducing VD × SF by reducing the vertical displacement can have a positive effect on running economy, but a concurrent reduction in CoMh may diminish the positive effect. Midterm and long-term effects of altering the technique should also be studied.
Collapse
Affiliation(s)
- Kjartan Halvorsen
- Division of Medical Engineering, School of Technology and Health, KTH Royal, Institute of Technology, Stockholm, Sweden.
| | | | | |
Collapse
|
37
|
Clemente Suárez VJ, González-Ravé JM. Four weeks of training with different aerobic workload distributions--effect on aerobic performance. Eur J Sport Sci 2011; 14 Suppl 1:S1-7. [PMID: 24444193 DOI: 10.1080/17461391.2011.635708] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/15/2022]
Abstract
Although numerous authors have studied the effect of different training procedures on athlete's resistance performance, there are no studies on how the improvement of aerobic resistance is affected by the distribution of training loads. This research sets out to analyse the effectiveness on aerobic activity of distributions with a constant load (CON) and with increments in intensity (INC) over a 4-week period. A total of 30 athletes took part in the analysis (38.7 ± 9.8 years; 174.7 ± 6.5 cm; 72.0 ± 9.8 kg). They were divided into 3 groups of 10 each. One group followed a training plan with a CON distribution and another with an INC distribution. Both groups performed at the same volume and intensity, the only difference between them being the distribution of load over the 4 weeks. The third group trained with a free load distribution during this time. Improvement in VO2max and ventilatory thresholds (VT1 and VT2) was analysed before and after the 4-week training period. There was no modification of the VO2max in any of the training programmes. The FRE and INC groups showed a significant decrease (p<0.05) in their VO2 in VT1, and in the CON group there was a significant reduction (p<0.05) in heart rate in VT2. These results show how training periodisation produces different improvement on performance and demonstrate the effectiveness of periodisated programmes, because periodisated programmes obtain equal or higher adaptations with lower training volumes than non-periodisated programmes.
Collapse
|