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Golf is such a difficult sport because the lie on which the ball is sitting is very rarely perfectly flat.

Different ground undulations will throw up an incredibly varied amount of different grass and slope conditions. One of the most common is a side hill lie.

When the ball comes to rest on the side of a slope, the impact will be affected and therefore the club used may have to change. The reason the impact characteristics will change has firstly to do with face plane tilt. When the ball is on a flat lie and the club sits with the leading edge flush to the floor and the club face aims down the target line. When the slope tilts left or right so will the club face. Because the club face is tilted backward with loft when the lie angle changes, so will the aim of the club face. When the toe of the club is raised, the face will point left. When the heel of the club is raised, the face will point right. These factors will obviously have a huge impact on where the ball will travel.

If a ball is on a side hill lie, its relative distance from the golfer will change. A ball on an uphill lie will be closer whilst a ball on a downhill lie will be further away. This has a big difference on the length of club which can be used which will therefore have a difference on the distance a ball will travel. This is why changing clubs will be necessary on most occasions when playing from sloping lies. A combination of face plane tilt and lie angle can drastically affect the direction and distance a ball will travel.

Because of the direct impact made to the club face, golfers will find it very difficult to keep everything the same. Adaptions must be made or the resulting shot will suffer as a result.

When playing off a side hill lie, the swing will have to alter slightly. A ball above the feet will require a slightly flatter, more rounded plane whilst the ball sitting below the feet will require a more upright swing. A combination of club and swing change will be required.

Although playing safe in some circumstances is recommended, if correct compensations are made with club selection and swing there is no reason why most golfers cannot change the way they play these shots. Changing the club when the ball is on a side hill lie will be required for most shots.