There is a growing, concern about children spending too much time sitting indoors in stead of playing outdoors. Recently it has been focused on how the natural environment affords possibilities and challenges for the children to explore their own abilities for exercise and mastering. Studies have shown how children's play in the natural environment stimulates their motor fitness. Other learning effects on linguistic and conceptual context, spatial perception and biological knowledge have also been noticed. An experimental study was carried out with 5 and 6 years old preschool children. The experimental group (N=46) was given motor training through playing in the natural environment. The physical landscape, vegetation and topography, was the arena for allround activities and free play. The experimental group visited the arena 1-2 hours every day when they attended the kindergarten. The reference group (N=29) was similar to the experimental group in age and living conditions. The reference group was attending normal kindergarten activities, but visited the natural environment only occasionally. The study lasted for 9 months. Both groups were tested before and after the implementation of the study. As testing methods the Eurofit Motor Fitness Test was applied. Preliminary results show a better improvement in mnotor fitness in the experimental group compared to the reference group. Significant differences (p<.ol were="" found="" in="" coordination="" balance="" skills="" and="" agility.="" age="" maturation="" related="" competencies="" such="" as="" body="" strength="" flexibility="" improved="" all="" groups="" but="" do="" not="" show="" similar="" significant="" differences="" between="" the="" groups.="" it="" was="" also="" noticed="" that="" amount="" of="" free="" play="" experimental="" group="" increased.="" there="" an="" considerable="" increase="" children="" interests="" knowledge="" nature.="" can="" be="" concluded="" by="" playing="" all-round="" activities="" natural="" environment="" motor="" fitness="" is="" improved.="" nature="" affords="" possibilities="" challenges="" for="" to="" explore="" their="" own="" abilities.="" feel="" more="" comfortable="" being="" about="" increases.="" study="" indicates="" a="" stimulating="" arena="" mastering="" learning="" processes="" pre-school="" children.="">