The Link Between Physical Activity and Brain Health in Healthy Adults

Measured with ELISA kit (e.g., R&D Systems, Cat. #DY248). Higher BDNF reflects greater neurotrophic support.

Assayed by high-sensitivity ELISA (e.g., Cusabio, Cat. #CSB-E13913h). Greater tau concentration indicates increased axonal injury or neurodegeneration.

Volume extracted with FreeSurfer; Larger values indicate greater hippocampal integrity

Fisher-Z transformed correlation computed with CONN; Higher values indicate stronger connectivity

Attention assessed with Wechsler Adult Intelligence Scale-IV Digit Span Forward subtest; Maximum correctly repeated digit sequence recorded. Higher scores indicate better attention/short-term memory capacity.

Visual attention and processing speed measured by TMT-A; time to connect 25 numbers in ascending order recorded. Shorter times indicate better performance.

Working memory measured with WAIS-IV Digit Span Backward; Longest correctly repeated backward sequence recorded. Higher scores indicate better working memory.

Executive function (set-shifting) assessed by TMT-B; Time to alternately connect numbers and letters recorded. Shorter times indicate better executive control.

Phonemic fluency tested with Controlled Oral Word Association Test (letters F, A, S, 60 s each); total correct words across three letters. Higher counts indicate better executive retrieval fluency.

Inhibition assessed with Golden Stroop test; The count of completions within 45 seconds is recorded. Lower times reflect better inhibitory control.

10-minute screening of global cognition covering memory, attention, language, visuospatial, and executive domains. Values ≥ 26 are considered normal. Higher scores indicate better cognition.

Genomic DNA isolated from EDTA whole blood; APOE genotyping by TaqMan SNP assays rs429358 and rs7412. Any ε4-containing genotype (ε2/ε4, ε3/ε4, ε4/ε4) classified as "ε4 carrier". Higher counts = higher ε4 prevalence.

Cardiopulmonary exercise test performed on treadmill using Ramp incremental ramp. Breath-by-breath gas exchange collected via metabolic cart. VO₂max defined as the highest 30-s average during the test; Higher values indicate better cardiorespiratory fitness.

Device worn on non-dominant wrist 24 h/day for 7 consecutive days. Raw data (100 Hz) processed in ActiLife with 10 s epochs; Freedson adult cut-points ≥ 1 952 counts·min-¹ define MVPA. Higher values indicate greater physical activity.

Height measured to 0.1 cm with height measuring rod. Weight obtained from InBody system. BMI = weight ÷ height². Higher BMI indicates greater overall adiposity.

Participants perform two maximal isometric mid-thigh pulls on calibrated dynamometer with 60 s rest. The higher of two trials recorded as peak force. Greater values indicate stronger lower-limb strength.

Standing posture, shoulder neutral, elbow extended. Two maximal squeezes per hand with dynamometer; 30 s rest between trials. Best value used for analysis. Higher values reflect greater grip strength.

Participants stand up from a 45-cm chair, walk 3 m, turn, return, and sit; time recorded by timers. Two trials with 1 min rest; Shorter time retained. Lower times represent better agility.

Balance and speed assessed on TANITA analyzer in eyes-open seated posture; Stand-up as fast as possible when signaled, repeat 3 times to get an optimal value; Manufacturer's composite stability index automatically computed (range 0-100). One 30-s trial; higher scores denote better balance.

Participants barefoot, InBody 770 provides whole-body fat percentage derived from segmental impedance; Higher values denote greater adiposity.

Analyzer outputs total skeletal muscle mass. Greater values indicate higher muscularity.

Measured at end-expiration; two readings within 1 cm averaged. Larger values indicate central adiposity.

Two readings averaged; used with waist girth to compute waist-to-hip ratio.

Fasting venous blood; triglycerides quantified on chemistry analyzer with glycerol phosphate oxidase method. Higher values indicate greater dyslipidemia risk.

Chemistry analyzer; Cholesterol esterase/oxidase method. Higher levels indicate increased cardiovascular risk.

Selective detergent method. Higher HDL is considered protective.

LDL-C = total-C - HDL-C - (triglycerides ÷ 5). Higher LDL indicates greater atherogenic risk.

Serum 25-hydroxyvitamin D concentration measured by chemiluminescent immunoassay (ng/mL)

Sedentary time defined as < 100 counts·min-¹ in vector-magnitudes; summed across valid waking wear days (≥ 10 h/day). Larger values denote more sedentary lifestyle.

Sleep/wake scored with Cole-Kripke algorithm; average total sleep time across nights with ≥ 160 min valid sleep. Longer duration indicates better sleep quantity.

Four IPAQ domains are summed; for each activity, minutes are multiplied by the corresponding MET value and then summed. Higher values indicate greater total energy expenditure.

Each of the 14 items is scored 0 or 1 and summed (total 0-14). A score ≥ 9 is considered high adherence. Higher scores indicate greater adherence to the Mediterranean dietary pattern.