Table 4.
Association of physical activity (PA) and protein intake interaction as categorical and continuous variables with physical function assessment at baseline and 3-year follow-up*
(Mean values and standard deviations; β values with their standard errors)
| PA < 2·5 h/week; protein < 1·1 g/kg g/kg BW (n 147) | PA < 2·5 h/week; protein ≥ 1·1 g/kg g/kg BW (n 46) | PA ≥ 2·5 h/week; protein < 1·1 g/kg BW (n 240) | PA ≥ 2·5 h/week; protein ≥ 1·1 g/kg BW (n 119) | PA and protein intake interaction continuous variable (n 552) | |||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Mean | sd | Mean | sd | Mean | sd | Mean | sd | β | se | P † | P ‡ | P § | |||||
| Hand grip strength (kg) | |||||||||||||||||
| Baseline | 26·1 | 0·5 | 24·2 | 0·9 | 25·8 | 0·4 | 24·1 | 0·6 | 0·020 | 0·125 | 0·282 | 0·205 | 0·638 | ||||
| At 3 years | 24·9 | 6·1 | 25·0 | 5·6 | 25·2 | 4·8 | 24·1 | 5·0 | –0·008 | 0·05 | 0·718 | 0·896 | 0·852 | ||||
| Change | –1·0 | 0·42 | 0·34 | 0·78 | –1·15 | 0·32 | –0·29 | 0·47 | –0·030 | 0·053 | 0·274 | 0·250 | 0·511 | ||||
| Hand grip strength adjusted for BMI (kg/m2) | |||||||||||||||||
| Baseline | 0·89 | 0·02 | 1·0 | 0·4 | 0·95 | 0·1 | 1·1 | 0·2 | 0·140 | 0·003 | 0·019 | 0·047 | 0·001 | ||||
| At 3 years | 0·83 | 0·25 | 0·88 | 0·24 | 1·00 | 0·25 | 0·92 | 0·20 | 0·087 | 0·003 | 0·001 | 0·001 | 0·046 | ||||
| Change | –0·04 | 0·01 | 0·02 | 0·03 | –0·05 | 0·01 | 0·04 | 0·01 | –0·069 | 0·002 | 0·083 | 0·046 | 0·139 | ||||
| Knee extension (Newtons) | |||||||||||||||||
| Baseline | 291 | 7·8 | 277 | 13·2 | 304 | 5·9 | 289 | 8·5 | 0·090 | 0·929 | 0·211 | 0·115 | 0·054 | ||||
| Chair rises in 20 s | |||||||||||||||||
| Baseline | 6·9 | 0·3 | 8·2 | 0·5 | 7·8 | 0·2 | 8·6 | 0·3 | 0·050 | 0·048 | 0·035 | 0·048 | 0·273 | ||||
| At 3 years | 7·7 | 3·1 | 8·6 | 3·1 | 8·4 | 3·3 | 9·8 | 2·6 | 0·190 | 0·030 | 0·008 | 0·002 | 0·001 | ||||
| Change | 0·01 | 0·04 | 0·00 | 0·07 | 0·02 | 0·03 | –0·09 | 0·03 | 0·088 | 0·045 | 0·913 | 0·897 | 0·057 | ||||
| Tandem walk speed over 6 m (m/s) | |||||||||||||||||
| Baseline | 0·29 | 0·04 | 0·34 | 0·07 | 0·35 | 0·03 | 0·32 | 0·04 | 0·049 | 0·003 | 0·603 | 0·779 | 0·304 | ||||
| At 3 years | 0·31 | 0·12 | 0·33 | 0·11 | 0·33 | 0·10 | 0·33 | 0·10 | 0·048 | 0·142 | 0·441 | 0·489 | 0·302 | ||||
| Change | –0·07 | 0·04 | –0·02 | 0·07 | –0·03 | 0·03 | 0·03 | 0·04 | –0·042 | 0·004 | 0·786 | 0·788 | 0·396 | ||||
| Walking speed over 10 m (m/s) | |||||||||||||||||
| Baseline | 1·50 | 0·03 | 1·73 | 0·06 | 1·69 | 0·02 | 1·79 | 0·04 | 0·205 | 0·004 | <0·001 | 0·010 | <0·001 | ||||
| At 3 years | 1·47 | 0·03 | 1·54 | 0·02 | 1·55 | 0·05 | 1·62 | 0·03 | 0·143 | 0·004 | 0·027 | 0·039 | 0·002 | ||||
| Change | –0·08 | 0·03 | –0·17 | 0·05 | –0·11 | 0·02 | –0·13 | 0·03 | –0·586 | 0·004 | 0·570 | 0·486 | 0·558 | ||||
| Standing on one leg for maximum 30 s | |||||||||||||||||
| Baseline | 15·6 | 1·0 | 19·2 | 2·0 | 19·0 | 0·8 | 22·0 | 1·2 | 0·106 | 0·110 | 0·002 | 0·012 | 0·014 | ||||
| At 3 years | 16·1 | 0·9 | 16·8 | 0·7 | 18·0 | 1·5 | 20·1 | 1·1 | 0·098 | 0·017 | 0·071 | 0·078 | 0·289 | ||||
| Change | –0·3 | 1·2 | –0·2 | 2·2 | –2·3 | 0·9 | –3·0 | 1·4 | –0·012 | 0·118 | 0·418 | 0·361 | 0·801 | ||||
| Able to perform squat (% of women) | |||||||||||||||||
| Baseline | 55 | 77 | 67 | 93 | 0·118 | 0·002 | 0·003 | 0·048 | 0·050 | ||||||||
| At 3 years | 83 | 88 | 91 | 94 | 0·105 | 0·003 | 0·241 | 0·113 | 0·022 | ||||||||
| Change | 20 | –15 | 29 | –10 | 0·057 | 0·004 | 0·343 | 0·330 | 0·218 | ||||||||
| Modified SPPB (calculated score) | |||||||||||||||||
| Baseline | 5·4 | 1·7 | 6·2 | 1·9 | 6·2 | 1·5 | 6·5 | 1·7 | 0·177 | 0·040 | <0·001 | <0·001 | <0·001 | ||||
| At 3 years | 7·3 | 1·8 | 7·4 | 1·8 | 7·6 | 1·6 | 8·2 | 1·6 | 0·089 | 0·020 | 0·018 | 0·010 | 0·043 | ||||
| Change | 1·8 | 2·2 | 1·2 | 2·2 | 1·4 | 1·8 | 1·5 | 2·1 | –0·125 | 0·027 | 0·112 | 0·074 | 0·098 | ||||
| Lean mass (kg) | |||||||||||||||||
| Baseline | 41·0 | 4·5 | 38·8 | 3·5 | 40·4 | 4·3 | 39·0 | 3·8 | 0·096 | 0·022 | 0·685 | 0·710 | 0·121 | ||||
| At 3 years | 41·2 | 5·0 | 40·3 | 4·5 | 38·9 | 2·5 | 39·1 | 4·0 | 0·178 | 0·012 | <0·001 | <0·001 | 0·311 | ||||
| Change | 0·2 | 0·1 | –0·1 | 0·2 | 0·07 | 0·11 | 0·07 | 0·17 | –0·025 | 1·82 | 0·432 | 0·421 | 0·592 | ||||
| RSMI (kg/m2) | |||||||||||||||||
| Baseline | 6·5 | 0·4 | 6·7 | 0·6 | 6·8 | 0·5 | 7·0 | 0·6 | 0·069 | 0·007 | <0·001 | <0·001 | 0·127 | ||||
| At 3 years | 6·8 | 0·8 | 6·6 | 0·6 | 6·4 | 0·5 | 6·6 | 0·6 | –0·057 | 0·008 | <0·001 | <0·001 | 0·277 | ||||
| Change | 0·0 | 0·4 | 0·1 | 0·2 | –0·1 | 0·3 | 0·0 | 0·3 | 0·023 | 0·005 | 0·434 | 0·537 | 0·626 | ||||
| Fat mass (kg) | |||||||||||||||||
| Baseline | 33·6 | 8·2 | 23·8 | 6·6 | 29·4 | 8·4 | 24·2 | 6·2 | –0·206 | 0·089 | <0·001 | <0·001 | <0·001 | ||||
| At 3 years | 33·0 | 9·4 | 29·7 | 8·6 | 22·9 | 6·5 | 23·8 | 6·3 | –0·198 | 0·097 | <0·001 | <0·001 | <0·001 | ||||
| Change | 0·05 | 3·12 | 0·08 | 3·21 | –0·94 | 2·31 | –0·19 | 2·18 | –0·095 | 3·431 | 0·487 | 0·605 | 0·040 | ||||
BW, body weight; SPPB, short physical performance battery; RSMI, relative skeletal muscle index; UNIANOVA, univariate ANOVA.
UNIANOVA was used to calculate mean values and standard deviations adjusted. Multiple regression analysis was used to calculate β-coefficient and standard error. Model 1 was adjusted for age and energy intake. Model 2 was adjusted for age, energy intake (kJ), smoking (yes, no), hormone therapy (yes, no), rheumatoid arthritis, baseline height (m), income per month (euros) and intensity of PA. At 3 years of follow-up, analyses were adjusted for absolute changes in physical function, muscle mass and study group (Ca and vitamin D intervention).
Mean values and standard deviations calculated from UNIANOVA adjusted for variables in model 1.
Mean values and standard deviation calculated from UNIANOVA adjusted for variables in model 2.
Calculated from multiple regression analysis, regression coefficient adjusted for variables in model 2.