Increased co-contraction reaction during a surface perturbation is associated with unsuccessful postural control among older adults
Abstract Background As a strategy to maintain postural control, the stiffening strategy (agonist-antagonist co-contractions) is often considered dysfunctional and associated with poor physical capacity. The aim was to investigate whether increased stiffening is associated with unsuccessful postural...
| Main Authors: | , , , , , |
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| Format: | Article |
| Language: | English |
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BMC
2022-05-01
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| Series: | BMC Geriatrics |
| Subjects: | |
| Online Access: | https://doi.org/10.1186/s12877-022-03123-2 |
| _version_ | 1828323334711934976 |
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| author | Jimmy Falk Viktor Strandkvist Mascha Pauelsen Irene Vikman Lars Nyberg Ulrik Röijezon |
| author_facet | Jimmy Falk Viktor Strandkvist Mascha Pauelsen Irene Vikman Lars Nyberg Ulrik Röijezon |
| author_sort | Jimmy Falk |
| collection | DOAJ |
| description | Abstract Background As a strategy to maintain postural control, the stiffening strategy (agonist-antagonist co-contractions) is often considered dysfunctional and associated with poor physical capacity. The aim was to investigate whether increased stiffening is associated with unsuccessful postural control during an unpredictable surface perturbation, and which sensory and motor variables that explain postural stiffening. Methods A sample of 34 older adults, 75.8 ± 3.8 years, was subjected to an unpredicted surface perturbation with the postural task to keep a feet-in-place strategy. The participants also completed a thorough sensory- and motor test protocol. During the surface perturbation, electromyography was measured from tibialis anterior and gastrocnemius to further calculate a co-contraction index during the feed-forward and feedback period. A binary logistic regression was done with the nominal variable, if the participant succeeded in the postural task or not, set as dependent variable and the co-contraction indexes set as independent variables. Further, the variables from the sensory and motor testing were set as independent variables in two separate Orthogonal Projections of Latent Structures (OPLS)-models, one with the feed-forward- and the other with the feedback co-contraction index as dependent variable. Results Higher levels of ankle joint stiffening during the feedback, but not the feed-forward period was associated with postural task failure. Feedback stiffening was explained by having slow non-postural reaction times, poor leg muscle strength and being female whereas feed-forward stiffening was not explained by sensory and motor variables. Conclusions When subjected to an unpredicted surface perturbation, individuals with higher feedback stiffening had poorer postural control outcome, which was explained by poorer physical capacity. The level of feed-forward stiffening prior the perturbation was not associated with postural control outcome nor the investigated sensory and motor variables. The intricate causal relationships between physical capacity, stiffening and postural task success remains subject for future research. |
| first_indexed | 2024-04-13T18:51:37Z |
| format | Article |
| id | doaj.art-418ad21080b240bab58844cabd5f6fff |
| institution | Directory Open Access Journal |
| issn | 1471-2318 |
| language | English |
| last_indexed | 2024-04-13T18:51:37Z |
| publishDate | 2022-05-01 |
| publisher | BMC |
| record_format | Article |
| series | BMC Geriatrics |
| spelling | doaj.art-418ad21080b240bab58844cabd5f6fff2022-12-22T02:34:24ZengBMCBMC Geriatrics1471-23182022-05-0122111010.1186/s12877-022-03123-2Increased co-contraction reaction during a surface perturbation is associated with unsuccessful postural control among older adultsJimmy Falk0Viktor Strandkvist1Mascha Pauelsen2Irene Vikman3Lars Nyberg4Ulrik Röijezon5Department of Health, Education and Technology, Luleå University of TechnologyDepartment of Health, Education and Technology, Luleå University of TechnologyDepartment of Health, Education and Technology, Luleå University of TechnologyDepartment of Health, Education and Technology, Luleå University of TechnologyDepartment of Health, Education and Technology, Luleå University of TechnologyDepartment of Health, Education and Technology, Luleå University of TechnologyAbstract Background As a strategy to maintain postural control, the stiffening strategy (agonist-antagonist co-contractions) is often considered dysfunctional and associated with poor physical capacity. The aim was to investigate whether increased stiffening is associated with unsuccessful postural control during an unpredictable surface perturbation, and which sensory and motor variables that explain postural stiffening. Methods A sample of 34 older adults, 75.8 ± 3.8 years, was subjected to an unpredicted surface perturbation with the postural task to keep a feet-in-place strategy. The participants also completed a thorough sensory- and motor test protocol. During the surface perturbation, electromyography was measured from tibialis anterior and gastrocnemius to further calculate a co-contraction index during the feed-forward and feedback period. A binary logistic regression was done with the nominal variable, if the participant succeeded in the postural task or not, set as dependent variable and the co-contraction indexes set as independent variables. Further, the variables from the sensory and motor testing were set as independent variables in two separate Orthogonal Projections of Latent Structures (OPLS)-models, one with the feed-forward- and the other with the feedback co-contraction index as dependent variable. Results Higher levels of ankle joint stiffening during the feedback, but not the feed-forward period was associated with postural task failure. Feedback stiffening was explained by having slow non-postural reaction times, poor leg muscle strength and being female whereas feed-forward stiffening was not explained by sensory and motor variables. Conclusions When subjected to an unpredicted surface perturbation, individuals with higher feedback stiffening had poorer postural control outcome, which was explained by poorer physical capacity. The level of feed-forward stiffening prior the perturbation was not associated with postural control outcome nor the investigated sensory and motor variables. The intricate causal relationships between physical capacity, stiffening and postural task success remains subject for future research.https://doi.org/10.1186/s12877-022-03123-2AgeingBalanceCo-contraction indexElectromyographyFallsSensorimotor |
| spellingShingle | Jimmy Falk Viktor Strandkvist Mascha Pauelsen Irene Vikman Lars Nyberg Ulrik Röijezon Increased co-contraction reaction during a surface perturbation is associated with unsuccessful postural control among older adults BMC Geriatrics Ageing Balance Co-contraction index Electromyography Falls Sensorimotor |
| title | Increased co-contraction reaction during a surface perturbation is associated with unsuccessful postural control among older adults |
| title_full | Increased co-contraction reaction during a surface perturbation is associated with unsuccessful postural control among older adults |
| title_fullStr | Increased co-contraction reaction during a surface perturbation is associated with unsuccessful postural control among older adults |
| title_full_unstemmed | Increased co-contraction reaction during a surface perturbation is associated with unsuccessful postural control among older adults |
| title_short | Increased co-contraction reaction during a surface perturbation is associated with unsuccessful postural control among older adults |
| title_sort | increased co contraction reaction during a surface perturbation is associated with unsuccessful postural control among older adults |
| topic | Ageing Balance Co-contraction index Electromyography Falls Sensorimotor |
| url | https://doi.org/10.1186/s12877-022-03123-2 |
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