Working with the cross-country ski ergometer does not require any prior knowledge of winter sports, the technique is beginner-friendly and quick to learn. However, there are a few points to bear in mind: Firstly, stand with your feet slightly more than shoulder-width apart (how close you stand to the device is a matter of taste, although taller people usually prefer a greater distance in order to achieve a full arm extension at the starting point and therefore ultimately a longer stroke). The hands should also be just outside the shoulders when gripping the handles. As the handles of the device are attached to freely movable hinges, you can easily rotate them to your optimum position. The edges of the hand, including the little finger, should be placed on the thickened end of the handle, allowing more pressure to be applied. At the beginning of the pull, the entire body is stretched, only the arms remain slightly bent, the handles are now pulled downwards at an angle until the hands are just below the knees (a V-shaped curve, where the hands move sideways away from the body, is avoided). At the lowest point, the elbows are fully extended while the knees are minimally bent (comparable to the starting position of a jump). In the return phase, the body straightens up again completely, synchronised with the backswing of the arms. Lifting your heels off the ground is perfectly fine, especially at higher speeds.

Attention:
Do not turn every repetition into a squat, as this will tire your legs too quickly. Take a deep breath before each pull on the machine and keep the abdominal muscles under constant tension.

Lighten/Harden:
The intensity is controlled by adjusting the air valve. The higher the lever is moved on the scale (1-10), the wider the flap opens and the more air can flow into the bike. More air means more resistance in the initial phase of the pull (comparable to a higher pedalling resistance in the higher gears on a bicycle). It is important to find a setting at which a continuous and controlled pressure can be maintained. If the setting is too high, the air resistance initially has to be overcome with an excessively strong pull and the remaining range of motion "runs into nothing", which is a waste of energy. If you pay attention to the background noise, you will get a suitable indicator: the aim should be to achieve the smoothest possible whirring with only slight peaks in the initial phase of the pull. Most exercisers tend to over-optimise the resistance setting. As is so often the case, less is more; levels 6-7 work well for men and 4-6 for women, with exceptions for particularly heavy and strong athletes.

Variant:
The double pole technique is usually used for training, which means that both arms work in synchronisation with each other. The diagonal technique, in which the arms are used alternately, is less common but can be used as a variation. It achieves lower speeds than the simultaneous use of the arms, but is certainly suitable as an occasional training stimulus, which above all creates a healthy rotation of the spine and a strain on the lateral trunk muscles. The diagonal technique can also correct imbalances in unevenly developed back and arm muscles (e.g. after injuries).

1 cross-country ski ergometer

Working with the cross-country ski ergometer does not require any prior knowledge of winter sports, the technique is beginner-friendly and quick to learn. However, there are a few points to bear in mind: Firstly, stand with your feet slightly more than shoulder-width apart (how close you stand to the device is a matter of taste, although taller people usually prefer a greater distance in order to achieve a full arm extension at the starting point and therefore ultimately a longer stroke). The hands should also be just outside the shoulders when gripping the handles. As the handles of the device are attached to freely movable hinges, you can easily rotate them to your optimum position. The edges of the hand, including the little finger, should be placed on the thickened end of the handle, allowing more pressure to be applied. At the beginning of the pull, the entire body is stretched, only the arms remain slightly bent, the handles are now pulled downwards at an angle until the hands are just below the knees (a V-shaped curve, where the hands move sideways away from the body, is avoided). At the lowest point, the elbows are fully extended while the knees are minimally bent (comparable to the starting position of a jump). In the return phase, the body straightens up again completely, synchronised with the backswing of the arms. Lifting your heels off the ground is perfectly fine, especially at higher speeds.

Attention:
Do not turn every repetition into a squat, as this will tire your legs too quickly. Take a deep breath before each pull on the machine and keep the abdominal muscles under constant tension.

Lighten/Harden:
The intensity is controlled by adjusting the air valve. The higher the lever is moved on the scale (1-10), the wider the flap opens and the more air can flow into the bike. More air means more resistance in the initial phase of the pull (comparable to a higher pedalling resistance in the higher gears on a bicycle). It is important to find a setting at which a continuous and controlled pressure can be maintained. If the setting is too high, the air resistance initially has to be overcome with an excessively strong pull and the remaining range of motion "runs into nothing", which is a waste of energy. If you pay attention to the background noise, you will get a suitable indicator: the aim should be to achieve the smoothest possible whirring with only slight peaks in the initial phase of the pull. Most exercisers tend to over-optimise the resistance setting. As is so often the case, less is more; levels 6-7 work well for men and 4-6 for women, with exceptions for particularly heavy and strong athletes.

Variant:
The double pole technique is usually used for training, which means that both arms work in synchronisation with each other. The diagonal technique, in which the arms are used alternately, is less common but can be used as a variation. It achieves lower speeds than the simultaneous use of the arms, but is certainly suitable as an occasional training stimulus, which above all creates a healthy rotation of the spine and a strain on the lateral trunk muscles. The diagonal technique can also correct imbalances in unevenly developed back and arm muscles (e.g. after injuries).

1 cross-country ski ergometer

Working with the cross-country ski ergometer does not require any prior knowledge of winter sports, the technique is beginner-friendly and quick to learn. However, there are a few points to bear in mind: Firstly, stand with your feet slightly more than shoulder-width apart (how close you stand to the device is a matter of taste, although taller people usually prefer a greater distance in order to achieve a full arm extension at the starting point and therefore ultimately a longer stroke). The hands should also be just outside the shoulders when gripping the handles. As the handles of the device are attached to freely movable hinges, you can easily rotate them to your optimum position. The edges of the hand, including the little finger, should be placed on the thickened end of the handle, allowing more pressure to be applied. At the beginning of the pull, the entire body is stretched, only the arms remain slightly bent, the handles are now pulled downwards at an angle until the hands are just below the knees (a V-shaped curve, where the hands move sideways away from the body, is avoided). At the lowest point, the elbows are fully extended while the knees are minimally bent (comparable to the starting position of a jump). In the return phase, the body straightens up again completely, synchronised with the backswing of the arms. Lifting your heels off the ground is perfectly fine, especially at higher speeds.

Attention:
Do not turn every repetition into a squat, as this will tire your legs too quickly. Take a deep breath before each pull on the machine and keep the abdominal muscles under constant tension.

Lighten/Harden:
The intensity is controlled by adjusting the air valve. The higher the lever is moved on the scale (1-10), the wider the flap opens and the more air can flow into the bike. More air means more resistance in the initial phase of the pull (comparable to a higher pedalling resistance in the higher gears on a bicycle). It is important to find a setting at which a continuous and controlled pressure can be maintained. If the setting is too high, the air resistance initially has to be overcome with an excessively strong pull and the remaining range of motion "runs into nothing", which is a waste of energy. If you pay attention to the background noise, you will get a suitable indicator: the aim should be to achieve the smoothest possible whirring with only slight peaks in the initial phase of the pull. Most exercisers tend to over-optimise the resistance setting. As is so often the case, less is more; levels 6-7 work well for men and 4-6 for women, with exceptions for particularly heavy and strong athletes.

Variant:
The double pole technique is usually used for training, which means that both arms work in synchronisation with each other. The diagonal technique, in which the arms are used alternately, is less common but can be used as a variation. It achieves lower speeds than the simultaneous use of the arms, but is certainly suitable as an occasional training stimulus, which above all creates a healthy rotation of the spine and a strain on the lateral trunk muscles. The diagonal technique can also correct imbalances in unevenly developed back and arm muscles (e.g. after injuries).

1 cross-country ski ergometer

Working with the cross-country ski ergometer does not require any prior knowledge of winter sports, the technique is beginner-friendly and quick to learn. However, there are a few points to bear in mind: Firstly, stand with your feet slightly more than shoulder-width apart (how close you stand to the device is a matter of taste, although taller people usually prefer a greater distance in order to achieve a full arm extension at the starting point and therefore ultimately a longer stroke). The hands should also be just outside the shoulders when gripping the handles. As the handles of the device are attached to freely movable hinges, you can easily rotate them to your optimum position. The edges of the hand, including the little finger, should be placed on the thickened end of the handle, allowing more pressure to be applied. At the beginning of the pull, the entire body is stretched, only the arms remain slightly bent, the handles are now pulled downwards at an angle until the hands are just below the knees (a V-shaped curve, where the hands move sideways away from the body, is avoided). At the lowest point, the elbows are fully extended while the knees are minimally bent (comparable to the starting position of a jump). In the return phase, the body straightens up again completely, synchronised with the backswing of the arms. Lifting your heels off the ground is perfectly fine, especially at higher speeds.

Attention:
Do not turn every repetition into a squat, as this will tire your legs too quickly. Take a deep breath before each pull on the machine and keep the abdominal muscles under constant tension.

Lighten/Harden:
The intensity is controlled by adjusting the air valve. The higher the lever is moved on the scale (1-10), the wider the flap opens and the more air can flow into the bike. More air means more resistance in the initial phase of the pull (comparable to a higher pedalling resistance in the higher gears on a bicycle). It is important to find a setting at which a continuous and controlled pressure can be maintained. If the setting is too high, the air resistance initially has to be overcome with an excessively strong pull and the remaining range of motion "runs into nothing", which is a waste of energy. If you pay attention to the background noise, you will get a suitable indicator: the aim should be to achieve the smoothest possible whirring with only slight peaks in the initial phase of the pull. Most exercisers tend to over-optimise the resistance setting. As is so often the case, less is more; levels 6-7 work well for men and 4-6 for women, with exceptions for particularly heavy and strong athletes.

Variant:
The double pole technique is usually used for training, which means that both arms work in synchronisation with each other. The diagonal technique, in which the arms are used alternately, is less common but can be used as a variation. It achieves lower speeds than the simultaneous use of the arms, but is certainly suitable as an occasional training stimulus, which above all creates a healthy rotation of the spine and a strain on the lateral trunk muscles. The diagonal technique can also correct imbalances in unevenly developed back and arm muscles (e.g. after injuries).

1 cross-country ski ergometer

Working with the cross-country ski ergometer does not require any prior knowledge of winter sports, the technique is beginner-friendly and quick to learn. However, there are a few points to bear in mind: Firstly, stand with your feet slightly more than shoulder-width apart (how close you stand to the device is a matter of taste, although taller people usually prefer a greater distance in order to achieve a full arm extension at the starting point and therefore ultimately a longer stroke). The hands should also be just outside the shoulders when gripping the handles. As the handles of the device are attached to freely movable hinges, you can easily rotate them to your optimum position. The edges of the hand, including the little finger, should be placed on the thickened end of the handle, allowing more pressure to be applied. At the beginning of the pull, the entire body is stretched, only the arms remain slightly bent, the handles are now pulled downwards at an angle until the hands are just below the knees (a V-shaped curve, where the hands move sideways away from the body, is avoided). At the lowest point, the elbows are fully extended while the knees are minimally bent (comparable to the starting position of a jump). In the return phase, the body straightens up again completely, synchronised with the backswing of the arms. Lifting your heels off the ground is perfectly fine, especially at higher speeds.

Attention:
Do not turn every repetition into a squat, as this will tire your legs too quickly. Take a deep breath before each pull on the machine and keep the abdominal muscles under constant tension.

Lighten/Harden:
The intensity is controlled by adjusting the air valve. The higher the lever is moved on the scale (1-10), the wider the flap opens and the more air can flow into the bike. More air means more resistance in the initial phase of the pull (comparable to a higher pedalling resistance in the higher gears on a bicycle). It is important to find a setting at which a continuous and controlled pressure can be maintained. If the setting is too high, the air resistance initially has to be overcome with an excessively strong pull and the remaining range of motion "runs into nothing", which is a waste of energy. If you pay attention to the background noise, you will get a suitable indicator: the aim should be to achieve the smoothest possible whirring with only slight peaks in the initial phase of the pull. Most exercisers tend to over-optimise the resistance setting. As is so often the case, less is more; levels 6-7 work well for men and 4-6 for women, with exceptions for particularly heavy and strong athletes.

Variant:
The double pole technique is usually used for training, which means that both arms work in synchronisation with each other. The diagonal technique, in which the arms are used alternately, is less common but can be used as a variation. It achieves lower speeds than the simultaneous use of the arms, but is certainly suitable as an occasional training stimulus, which above all creates a healthy rotation of the spine and a strain on the lateral trunk muscles. The diagonal technique can also correct imbalances in unevenly developed back and arm muscles (e.g. after injuries).

1 cross-country ski ergometer

Working with the cross-country ski ergometer does not require any prior knowledge of winter sports, the technique is beginner-friendly and quick to learn. However, there are a few points to bear in mind: Firstly, stand with your feet slightly more than shoulder-width apart (how close you stand to the device is a matter of taste, although taller people usually prefer a greater distance in order to achieve a full arm extension at the starting point and therefore ultimately a longer stroke). The hands should also be just outside the shoulders when gripping the handles. As the handles of the device are attached to freely movable hinges, you can easily rotate them to your optimum position. The edges of the hand, including the little finger, should be placed on the thickened end of the handle, allowing more pressure to be applied. At the beginning of the pull, the entire body is stretched, only the arms remain slightly bent, the handles are now pulled downwards at an angle until the hands are just below the knees (a V-shaped curve, where the hands move sideways away from the body, is avoided). At the lowest point, the elbows are fully extended while the knees are minimally bent (comparable to the starting position of a jump). In the return phase, the body straightens up again completely, synchronised with the backswing of the arms. Lifting your heels off the ground is perfectly fine, especially at higher speeds.

Attention:
Do not turn every repetition into a squat, as this will tire your legs too quickly. Take a deep breath before each pull on the machine and keep the abdominal muscles under constant tension.

Lighten/Harden:
The intensity is controlled by adjusting the air valve. The higher the lever is moved on the scale (1-10), the wider the flap opens and the more air can flow into the bike. More air means more resistance in the initial phase of the pull (comparable to a higher pedalling resistance in the higher gears on a bicycle). It is important to find a setting at which a continuous and controlled pressure can be maintained. If the setting is too high, the air resistance initially has to be overcome with an excessively strong pull and the remaining range of motion "runs into nothing", which is a waste of energy. If you pay attention to the background noise, you will get a suitable indicator: the aim should be to achieve the smoothest possible whirring with only slight peaks in the initial phase of the pull. Most exercisers tend to over-optimise the resistance setting. As is so often the case, less is more; levels 6-7 work well for men and 4-6 for women, with exceptions for particularly heavy and strong athletes.

Variant:
The double pole technique is usually used for training, which means that both arms work in synchronisation with each other. The diagonal technique, in which the arms are used alternately, is less common but can be used as a variation. It achieves lower speeds than the simultaneous use of the arms, but is certainly suitable as an occasional training stimulus, which above all creates a healthy rotation of the spine and a strain on the lateral trunk muscles. The diagonal technique can also correct imbalances in unevenly developed back and arm muscles (e.g. after injuries).

1 cross-country ski ergometer

Sparring in a three-man team: two boxers and a referee. After a while, the roles are switched.

Participant:
1 pair of boxing gloves

Sparring between two participants, with one always taking the role of the attacker and the other the defender. In the next round, the roles are swapped. The attacker makes sure to constantly cut the defender's path (shorten the path) so that he can immediately move on to the next attack. The defender, for his part, tries to evade the attacker by moving in the shape of a banana.

Participant:
1 pair of boxing gloves

Sparring with restrictions, e.g. both boxers only use the lead hand.

Participant:
1 pair of boxing gloves

Two participants stand opposite each other. One participant moves to the side with a step. The feet remain shoulder-width apart, the foot closer to the direction of movement initiates the movement. The weight is on the balls of the feet, the steps are springy and gliding. The partner constantly tries to remain facing him and imitate all (arm) movements. After a while, the roles are swapped.

No material required

Two participants stand opposite each other on one leg and both hold their fists at head height. One participant sets the positions by jumping with one leg between the tyres laid out on the floor (identical tyre arrangement for both participants). The second participant tries to re-establish the same distance as quickly as possible. After a certain time, change the jumping leg and/or the rollers.

Per group:
8 tyres

Purpose
Training and testing of the throwing technique

Additional equipment
5 HG 85 throwing gun

Starting position
lying down, Stgw with empty magazine

Procedure

1. Sprint 50 m into a throwing position (target time 15 s)

2. 5 throws from different throwing distances

Conditions
4 hits and 3 different freely selectable throwing distances

Notes

• If no realistic HG targets are available, marked target areas can also be used (e.g.

• for reasons of efficiency, several throwers should be able to practise at the same time.

• with an increased routine, the requirements in terms of throwing distance should be increased.

Material per participant: Tenue CNM

Additional material: 6 G-discs with posts, 3 fanjons, 2 red/white marking tapes, 2 boxes with 16 HG 85 clay pellets

Cover a given distance (between 10-20 metres) as quickly as possible/at a sprint (if necessary, shuttle back and forth between the markers several times).

Lighten:
Lower speed.

Harden:
Higher speed.

Variant:
Do not sprint but change your gait between the markers (e.g. backwards, on all fours, crawling, etc.).

2 marinating cones/caps/colouring sticks

Stand upright on the balls of your feet with your knees slightly bent and your arms resting on your hips. Jump steadily in place (fast frequency) without putting your heels down (jump on your toes).

Attention:
Keep your upper body upright (keep your core tensed).

Lighten:
Smaller/less intense jumps.

Harden:
Larger/intensive jumps; additional weight (on the chest/shoulders, hold in the hands, hold in front).

Variation:
Pull the tips of the feet towards the knee (bend the feet) with each jump.

2 weight cuffs/short dumbbells/1 weight vest/weight disc/(medicine) ball/sandbag/fighting backpack ► Make the exercise more difficult (additional weight)

Stand upright on the balls of your feet with your feet shoulder-width apart, holding a skipping rope in your hands. Jump steadily in place and simultaneously swing the rope (under your feet and overhead), with the rope making two complete rotations during one jump (double jump).

Attention:
Do not put your heels down (jump on the balls of your feet/tips of your toes). Keep your upper body upright (tense your core). The rope is accelerated from the wrists (very fast circling) so that two rope rotations are possible during a jump.

Lighten:
Simple jumps (slower swinging - one rope rotation per jump).

Harden:
Additional weight (on the feet).

Variant I:
Pull the tips of your feet towards your knees (bend your feet) with each jump.

Note:
Two single jumps replace one double jump (1 double under = 2 x single rope jumps) in training. Instead of jumping rope, the knee lift (skipping) is often chosen as a substitute (no material required).

1 skipping rope

2 weight cuffs/1 weight waistcoat ► Make the exercise more difficult (additional weight)

Stand upright on the balls of your feet with your feet shoulder-width apart, holding a skipping rope in your hands. Jump steadily in place and simultaneously swing the rope (under your feet and overhead).

Attention:
Without putting your heels down (jumping on the balls of your feet/tips of your toes). Keep your upper body upright (tense your core).

Lighten:
Lower intensity (slower swinging).

Harden:
Higher intensity (very fast jumping); additional weight (on the feet).

Variant I:
Pull the tips of your feet towards your knees with each jump (bend your feet).
Variant II:
Integrate jump shapes: Double jumps, crossing arms, alternating left/right heel taps on the floor, straddle jumps, jumping in step position, alternating jumps, etc.

Note:
Two single jumps replace one double jump in training (1 double under = 2 x single rope jumps). Instead of jumping rope, the knee lift (skipping) is often chosen as a substitute (no material required).

1 skipping rope

2 weight cuffs/1 weight waistcoat ► Make the exercise more difficult (additional weight)

Stand on one leg on the balls of your feet (left leg), knees slightly bent and arms supported on your hips. Jump steadily in place (fast frequency) without putting your heel down (jump on your toes).

Attention:
Keep your upper body upright (tense your core).

Lighten:
Bend your knees less (greater angle), smaller/less intense jumps.

Harden:
Bend your knees more (smaller angle); bigger/more intense jumps; additional weight (on your chest/shoulders, hold in your hands, in front of you).

Variation:
Pull the tip of your foot towards your knee (bend your foot) with every jump.

1 weight cuff/weight vest/weight disc/(medicine) ball/sandbag/fighting backpack/2 dumbbells ► Make the exercise more difficult (additional weight)

Steady hopping in place on one leg (left) without putting your heel down completely. Every few repetitions (e.g. always after 5 small hops) perform a jump upwards (one-legged jump). The arms can support the jump by pulling them up and overhead when jumping from hip height.

Attention:
Keep your upper body upright (tense your core).

Lighten:
Smaller/less intense jumps into the air.

Harden:
Higher/intensive jumps; additional weight (on your chest/shoulders, hold in your hands, hold in front of you).

Variation:
Pull the tip of your foot towards your knee (bend your foot) with each jump.

1 weight cuff/weight vest/weight disc/(medicine) ball/sandbag/fighting backpack/2 dumbbells ► Make the exercise more difficult (additional weight)

Stand on one leg (left), with the free (right) leg raised (approximately right angle in the knee joint so that the knee is at about hip height in front of the body). Jump steadily in place, putting your heel down completely with each repetition.

Attention:
Keep your upper body upright (keep your core tensed).

Lighten:
Smaller/less intense jumps.

1 weight cuff/weight vest/weight disc/(medicine) ball/sandbag/fighting backpack/2 dumbbells ► Make the exercise more difficult (additional weight)

Stand upright on one leg (left), standing only on the front foot/ball of the foot, holding a skipping rope in your hands. Continuous one-legged hopping in place and simultaneous swinging of the rope (under the standing leg and overhead).

Attention:
Without putting down the heel (jumping on the ball of the foot/tips of the toes). Keep your upper body upright (tense your core).

Lighten:
Lower intensity (slower swing).

Harden:
Higher intensity (very fast jumping); additional weight (on the supporting leg).

Variant I:
Pull the tip of the foot towards the knee (bend the foot) with every jump.
Variant II:
Integrate jump forms: Double jumps, crossing your arms, tapping your heel on the floor, etc.

1 skipping rope

1 weight cuff/weight waistcoat ► to make the exercise more difficult (additional weight)

Stand on one leg on the balls of your feet (right leg), knees slightly bent and arms supported on your hips. Bounce steadily in place (fast frequency) without putting your heel down (jump off on your toes).

Attention:
Keep your upper body upright (keep your core tensed).

Lighten:
Bend your knees less (greater angle), smaller/less intense jumps.

Harden:
Bend your knees more (smaller angle); bigger/more intense jumps; additional weight (on your chest/shoulders, hold in your hands, in front of you).

Variation:
Pull the tip of your foot towards your knee (bend your foot) with every jump.

1 weight cuff/weight vest/weight disc/(medicine) ball/sandbag/fighting backpack/2 dumbbells ► Make the exercise more difficult (additional weight)

Steady hopping in place on one leg (right) without putting your heel down completely. Every few repetitions (e.g. always after 5 small hops) perform a jump upwards (one-legged jump). The arms can support the jump by pulling them up and overhead when jumping from hip height.

Attention:
Keep your upper body upright (tense your core).

Lighten:
Smaller/less intense jumps into the air.

Harden:
Higher/intensive jumps; additional weight (on your chest/shoulders, hold in your hands, hold in front of you).

Variation:
Pull the tip of your foot towards your knee (bend your foot) with each jump.

1 weight cuff/weight vest/weight disc/(medicine) ball/sandbag/fighting backpack/2 dumbbells ► Make the exercise more difficult (additional weight)

Stand on one leg (right), with the free (left) leg raised (approximately right angle in the knee joint so that the knee is at hip height in front of the body). Jump steadily in place, putting your heel down completely with each repetition.

Attention:
Keep your upper body upright (keep your core tensed).

Lighten:
Smaller/less intense jumps.

1 weight cuff/weight vest/weight disc/(medicine) ball/sandbag/fighting backpack/2 dumbbells ► Make the exercise more difficult (additional weight)

Stand upright on one leg (right), standing only on the front foot/ball of the foot, holding a skipping rope in your hands. Continuous one-legged hopping in place and simultaneous swinging of the rope (under the standing leg and overhead).

Attention:
Jump without putting your heel down (on the ball of your foot/tips of your toes). Keep your upper body upright (tense your core).

Lighten:
Lower intensity (slower swing).

Harden:
Higher intensity (very fast jumping); additional weight (on the supporting leg).

Variant I:
Pull the tip of the foot towards the knee (bend the foot) with every jump.
Variant II:
Integrate jump forms: Double jumps, crossing your arms, tapping your heel on the floor, etc.

1 skipping rope

1 weight cuff/weight waistcoat ► to make the exercise more difficult (additional weight)

Stand upright with your feet shoulder-width apart, hopping steadily in place. Alternately bend one leg during the two-legged small jump (raise the knee in front of the body to approximately hip height). Land on both legs (heels completely off the ground), keeping the ground contact time as short as possible before the next repetition. Support your arms on your hips or support the movement with your arms (arms bent and stretched - arm bent on the opposite side where the knee is raised - sprinter position).

Caution:
Keep your upper body upright (tense your core).

Lighten:
Smaller/less intense jumps (lift your knees less).

Harden:
Higher/more intense jumps; additional weight (on your chest/shoulders, hold in your hands, in front of you).

2 weight cuffs/short dumbbells/1 weight vest/weight disc/(medicine) ball/sandbag/fighting rucksack ► Make the exercise more difficult (additional weight)