Frailty reflects the heterogeneity in aging and may lead to the development of hypertension and heart disease, but the frailty-cardiovascular relation and whether physical activity modifies this relation in males and females is unclear. We tested if higher frailty was positively associated with hypertension and heart disease in males and females, and if habitual movement mediated this relation. The relation between baseline frailty with follow-up hypertension and heart disease was investigated using the Canadian Longitudinal Study on Aging at 3-year Follow-Up data (males: n=13095, females: n=13601). Frailty at baseline was determined via a 73-item deficit-based index, activity at follow-up via the Physical Activity Scale for the Elderly, and cardiovascular function was self-reported. Higher baseline frailty level was associated with a greater likelihood of hypertension and heart disease at follow-up, with covariate-adjusted odds ratios of 1.08-1.09 (all, p<0.001) for a 0.01 increase in frailty index score. Among males and females, sitting time and strenuous physical activity were independently associated with hypertension, with these activity behaviours being partial mediators (except males-sitting time) for the frailty-hypertension relation (explained 5-10% of relation). The strength of this relation was stronger among females. Only light-moderate activity partially mediated the relation (~6%) between frailty and heart disease in females, but no activity measure was a mediator for males. Higher frailty levels were associated with a greater incidence of hypertension and heart disease, and strategies that target increases in physical activity and reducing sitting may partially uncouple this relation with hypertension, particularly among females.