Nowadays cardio is rather archaic (which doesn't mean inefficient) method of body fat reduction. However, there have appeared many various solutions throughout the years, such as intervals in different forms (circuit training, crossfit, stations, alternate sprints, pulling the load, jumps). Classic aerobics cannot be forgotten, because intervals (especially highly-intensive) have many flaws, e.g. they can be impossible to achieve by some because of the physical condition problems.
What's more, we already know from research, that the benefits from moderate interval training (e.g. alternate marching and jogging) don't have to be spectacular, comparing to classic “cardio” (long-lasting effort of low intensity). People keep on searching for some marvellous new ways of getting rid of fat – instead of using proven methods – e.g. changing diet (calorific deficit) and lifestyle (physical activity, sport, riding bike instead of car...). Here are the most ridiculous methods of “reduction”.
Neoprene belt, thick layers of clothes and other methods of dehydration
According to adverts, the belt “can speed up burning of fat by 30%”. another variation is “sauna belt”. Unfortunately, there aren't any scientific studies, which would confirm its efficiency. Facts are following: neoprene belt is a great way of earning money by the sellers... and that's it. Metabolism during exercises increases one hundred times, what causes fifteen to twenty times higher level of heat release by muscles! Higher temperature causes sweating – which is the way of getting rid of excess amount of heat (evaporation). According to J.Gorski, releasing 1 litre of sweat is the cost of 580 kcal of heat . But nothing is free – we lose electrolytes (sodium, potassium, chloride) with sweat. Putting on warmer clothes – or using e.g. the neoprene belt, is nothing else but local overheating of the body. This way we impair the process of heat release through skin! Sweating is more intensive then, which means that we lose water and electrolytes. It's an archaic method of losing weight commonly used by wrestlers, boxers, Thai boxers, judokas, K-1 or MMA competitors.
Of course, during long-lasting physical effort causing dehydration you will lose 1-2 kg of weight – but there will be... no fat in it. For sportsmen such “reduction” from time to time is enough, as they have to achieve their competition weight for one moment – the control during competition (official weighing).
Ramon K., et. al checked: “Consumption of food by judokas 3 days before and during the competition day”. The aim of their work was the assessment of food and beverages intake, as well as energy expenditure 3 days before the competition among 21 females and 11 males training judo. […] Over half of them (52.1%) dehydrated themselves by training in air-proof and sweat-proof clothes, which caused intensive sweating. Almost 40% of the competitors limited drastically drank beverages, and 30.4% used sauna to dehydrate. […] The negative energy balance causes lower reserve of muscle glycogen, and negative fluid balance leads to chronic dehydration. Both changes may be the reason of lower effort abilities and health disorders”. 
Additionally, such actions may contribute to health problems:
For example, among the taekwon-do competitors in the time of “creating weight”:
11.4% suffered from dizziness,
10.8% happened to have headaches,
5.6% had heart rate disorders,
over 15% of those “creating weight” felt worse effort abilities,
17.1% felt worse special efficiency, mainly muscle strength (26.9%) and endurance (19.1%) .
To sum up:
“Overheating the body” intensifies the loss of water and electrolytes, not the subcutaneous or visceral (around the inner organs) fat. After completing the fluids, all the “lost weight” goes back to the previous state,
Overheating means worse release of heat, faster heart rate – heart-vessel complications may appear (especially among obese people),
Large loss of weight (water, electrolytes) causes health problems. The bigger loss – the more serious consequences may concern e.g. disturbing heart, cramps are possible to occur, worse concentration, dizziness, etc.
The worst idea is to overheat on hot days when humidity is high when using non-selective sympathomimetic substances (e.g. ephedrine), selective beta-mimetics (e.g. clebuterol, salbutamol), amphetamine analogues (e.g. phentermine) or substances with different efficiency (e.g. sibutramine).
The same rule concerns putting on additional layers of thermoactive clothes, thick cotton sweatshirts or using sauna. These are the methods which allow only for temporary dehydration, the reserves of body fat stay the same.
Cardio before, during and after strength workout
In each case, you have to remember about limiting the volume of aerobic workout because excessive activity in the aerobic zone (paradoxically) does not contribute to the loss of fatty tissue. It was proven in research done on runners. Running even 64 km a week in steady pace did not protect from gaining body fat. Long-lasting aerobic exercises before strength training may lower the efficiency of the strength session (decreased glycogen, influence on hormones, slower recovery after strength workout, antagonistic paths/processes in muscles mTOR vs PGC-1), and aerobic exercises done right after strength training may intensify micro injuries, decrease building strength and may cause inflammation in muscles. It was also stated that rise of strength in bench press in a mixed group, which did strength and endurance training (running) was smaller by over 9% comparing to volunteers doing strength training only. The increase of muscle mass was slightly higher in the strength training group comparing to the mixed training group (strength and running). Although, for leg press the results were similar – independently from group kind. Endurance training included running 2-3 x a week outdoors or on treadmill for 12 weeks. Strength training included 8 exercises of the whole body 2-3 x a week for 12 weeks .
When it comes to the reduction of body fat in the mentioned experiment, the best effects were achieved in the endurance group (1.4% less), worse in strength group (0.6% of fat less) and optimal in running with strength group (1.3% less).
Conclusions? If you think that strength training is not enough – add 1-2 interval sessions on the days free from strength workouts. The plans of such training have been described here many times. Well-trained people can think about intervals right after strength training.
This way you cause unphysiological local overload which can lead to the injury of ankle or knee. If you think you do light running training – just start running faster or try out any kind of intervals. Adding load makes no sense. If you have to – pull the load behind you, like strongmen competitors (they use trucks, planes, etc.), crossfit or MMA (load e.g. tire on a rope, chain, harness, etc.).
Running next to busy roads
Let's skip the aspect of safety, e.g. careless drivers who can hit you. When running in such place, you breath in toxic fumes (in large amount because during physical effort the gas exchange increases), which destroy your health – lungs, where heavy metals gather. Do you want to get ill? Keep on running next to busy roads. It doesn't matter that there has been progress in the area of limiting toxic compounds. Engines and their fumes are still dangerous for humans.
Running on empty stomach
It will be beneficial for only small amount of professionals who use sophisticated pharmaceuticals (protecting them from catabolism) and special diets (e.g. IF). For the rest of population it causes a lot of losses (e.g. muscle mass) and not so many benefits. Interval training connected with aerobic exercises done after 2-3 meals will be much better.