Handgrip is a complex functional movement which involves co-activation of many forearm flexor and extensor muscles (Johanson et al. 1998), with a small contribution from intrinsic hand muscles (Long et al. 1970). Several studies have shown that immersing the hand and forearm in cold water reduces handgrip maximum voluntary force (MVF) (e.g. Chi et al. 2012). However, in cold environments the forearm is often thermally protected with only the hand exposed when performing manual tasks. To our knowledge only one study has investigated the effects of cooling the hand alone on handgrip, which observed declines in MVF (Vincent & Tipton 1988). This result is surprising given the relatively small contribution of intrinsic hand muscles. Vincent and Tipton did not compare the effects of cooling and warming the hand alone vs. both hand and forearm upon handgrip MVF in the same individuals, which was the aim of the present study. The hypothesis was that handgrip MVF would decrease to a greater extent with both hand and forearm cooling. Twenty-four healthy subjects (15♂, 18-70 years), attended twice when either their right hand alone or hand and forearm was cooled and warmed using a CryocuffTM containing iced water at ~6°C, or warm water at ~45°C. The subject’s hand, or hand and arm was removed from the Cryocuff at 4-minute intervals and two handgrip MVF measurements obtained using a handgrip dynamometer (Camry Model EH101) after which the Cryocuff was re-applied. Skin temperature over first dorsal interosseous was monitored throughout the experiment and recorded immediately before each set of MVF measurements. The reported MVF is the maximum force exerted at each temperature point. Data were analysed using R (v3.2.3) and the LME4 package (Bates et al. 2015), using a mixed model approach. Temperature, gender and condition were fixed effects, with subject as a random effect, and by-subject random slopes for the effect of temperature. Cooling resulted in a decrease in handgrip MVF when both hand and forearm and hand alone were cooled (p<0.0001 for both conditions) although the decrease was significantly greater when hand and forearm were cooled (p<0.05). Whilst the greatest reduction in handgrip MVF was observed with hand and forearm cooling, significant decrements from hand only cooling MVF suggest that mechanisms other than, or in addition to, direct muscle cooling are involved. This has implications for manual work at cold temperatures. Furthermore, if cooling the foot results in analogous declines in maximal ankle dorsi- and plantar-flexion forces, this may contribute to the increase in indoor fall rates observed in older frail people in winter.