{
  "schema_version": 1,
  "id": "sitting-breaks-cognition-boundary-2026",
  "canonical_url": "https://brali-lifeos.github.io/evidence/sitting-breaks-cognition-boundary-2026/",
  "json_url": "https://brali-lifeos.github.io/evidence/sitting-breaks-cognition-boundary-2026/index.json",
  "decision": "watch",
  "decision_label": "Watch, do not prescribe",
  "reviewed_at": "2026-09-05",
  "reviewed_by": "Brali Evidence Reviewer",
  "source": {
    "title": "Acute cognitive effects of interruptions to prolonged sitting with brief standing or physical activity breaks: a systematic review and three-level meta-analysis",
    "url": "https://link.springer.com/article/10.1186/s12966-026-01953-6",
    "type": "systematic-review-meta-analysis",
    "doi": "10.1186/s12966-026-01953-6",
    "citation_text": "Zhuang M, Yin M, Liu Z, et al. International Journal of Behavioral Nutrition and Physical Activity. 2026;23:79.",
    "study_design": "Prospectively registered systematic review (PROSPERO CRD420251273873) following PRISMA. It searched five major databases through January 2026 for randomized crossover trials comparing prolonged sitting with brief standing or physical-activity interruptions and cognitive outcomes. Twenty-one trials involving 433 participants were included. A three-level random-effects meta-analysis and cluster-robust variance estimation addressed dependent effect sizes; risk of bias used RoB 2 and certainty used GRADE.",
    "population": "433 participants across 21 randomized crossover trials. Samples and protocols varied; exploratory subgroup analyses suggested differences by age and weight status, but the review explicitly judged these insufficient for prescriptive recommendations.",
    "intervention_or_exposure": "Brief standing or physical-activity interruptions during experimentally prolonged sitting, compared with uninterrupted sitting. Interruption frequency, duration, intensity and modality varied across studies.",
    "outcomes": [
      "Executive function",
      "Memory function",
      "Global cognition",
      "Information processing",
      "Attention",
      "GRADE certainty and exploratory protocol moderators"
    ]
  },
  "supported_claim": "The existing Brali sitting-break protocol has limited additional cognitive support: across randomized crossover studies, interrupting prolonged sitting was associated with small acute improvements in executive function and memory. Because certainty was low and attention/information-processing results were not clear, cognition should remain a secondary possible benefit rather than the reason or promise for the protocol.",
  "unsupported_or_overstated_claims": [
    "Movement breaks reliably improve attention or concentration; the pooled attention estimate was not beneficial.",
    "Movement breaks reliably improve overall cognition or information-processing speed.",
    "A specific break frequency is proven optimal for executive function or memory.",
    "Low-intensity walking is definitively superior to other feasible movement modes for cognition.",
    "The small acute cognitive effects translate into better workplace productivity, fewer errors, academic achievement, or long-term cognitive protection.",
    "The exploratory subgroup results establish who should use a more frequent or less frequent break schedule."
  ],
  "limitations": [
    "Only 21 crossover trials with 433 total participants were included, leaving many domain and subgroup estimates based on small evidence bases.",
    "GRADE certainty was low for executive function, memory, information processing and attention and very low for global cognition.",
    "The evidence concerns acute experimental responses, not long-term cognitive outcomes, productivity or real-world work performance.",
    "Intervention protocols varied substantially in frequency, intensity, duration and mode.",
    "Subgroup and meta-regression findings were exploratory and should not be converted into individualized dosing rules.",
    "Some apparently favorable domain estimates may be sensitive to the small number of studies and heterogeneous cognitive tasks."
  ],
  "target_hack_ids": [
    "break-up-prolonged-sitting"
  ],
  "target_protocol_ids": [
    "brali:break-up-prolonged-sitting"
  ],
  "risk_flags": [
    "health"
  ],
  "notes": "Evidence role: watch-level boundary for the existing protocol. Keep the action simple—interrupt long sitting with feasible brief movement—but do not sell the protocol as an attention or productivity hack and do not infer an exact timer from exploratory moderator analyses."
}